Go Back   The Ford Barn > General Discussion > Early V8 (1932-53)

Sponsored Links (Register now to hide all advertisements)

Reply
 
Thread Tools Display Modes
Old 01-31-2015, 11:58 AM   #1
4tford
Senior Member
 
4tford's Avatar
 
Join Date: May 2010
Location: Regina Canada
Posts: 1,314
Default Blower motor center main cap

looking for pros and cons of steel center main vs the bolt on strap. Will be for a Paxton blower motor 276 cu. in. Thanks Bill
4tford is offline   Reply With Quote
Old 01-31-2015, 12:14 PM   #2
scooder
Senior Member
 
Join Date: Jul 2010
Posts: 2,573
Default Re: Blower motor center main cap

Strap is cheap and easy to fit, steel main cap will need Line boring, not cheap.
Plenty of built flatheads out there with the strap.
How much pressure and abuse is the engine really gonna see?
Those centrifugal blowers don't have the low end thump of power off idle like a rootes blower, there generally more gentle build of power higher up.
Martin.
scooder is offline   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 01-31-2015, 05:58 PM   #3
Ol' Ron
Senior Member
 
Ol' Ron's Avatar
 
Join Date: May 2010
Location: Chester Vt
Posts: 7,084
Default Re: Blower motor center main cap

I waz gong to say the same thing, strap, properly installed should be good for 5lbs. Have a 294 going together with a Magnason blower and a strapped center main, so we'll find out.
Ol' Ron is offline   Reply With Quote
Old 01-31-2015, 06:42 PM   #4
Lawrie
Senior Member
 
Lawrie's Avatar
 
Join Date: May 2010
Location: Qld, Australia
Posts: 3,284
Default Re: Blower motor center main cap

We ran a 258 cu in engine in our dragster for a couple of seasons,Hilborn injection,no blower ,all stock 8ba stuff in the engine ,including the main caps,no strap,ran it up to 5700rpm, no worries,
Lawrie
Lawrie is offline   Reply With Quote
Old 01-31-2015, 08:22 PM   #5
quickchange34
Senior Member
 
quickchange34's Avatar
 
Join Date: May 2010
Location: charlottesville, Va.
Posts: 561
Default Re: Blower motor center main cap

You won't have any trouble with the strap until you get over ten pounds of boost,
quickchange34 is offline   Reply With Quote
Old 01-31-2015, 08:39 PM   #6
4tford
Senior Member
 
4tford's Avatar
 
Join Date: May 2010
Location: Regina Canada
Posts: 1,314
Default Re: Blower motor center main cap

Thanks guys for the good news. Usually when I have a chioce it needs to be the expansive one. The paxton was rebuilt by Paradise Wheels and I was told was 7 pound boost.
4tford is offline   Reply With Quote
Old 02-01-2015, 09:51 AM   #7
scooder
Senior Member
 
Join Date: Jul 2010
Posts: 2,573
Default Re: Blower motor center main cap

That seven pounds is just guess work, not an accurate number. The amount of boost pressure in any engine is dependant on lots of things, tis only a ball park figure. You have to measure the pressure on the engine it's gonna live on. So be sure to fit a pressure guage to see what your actually getting. If it goes to high your heading for expensive parts bills.
Out of interest what's the rest of the engine spec?
Martin.
scooder is offline   Reply With Quote
Old 02-05-2015, 03:26 PM   #8
lonewolf
Senior Member
 
Join Date: May 2010
Location: Michigan
Posts: 389
Default Re: Blower motor center main cap

Quote:
Originally Posted by Ol' Ron View Post
I waz gong to say the same thing, strap, properly installed should be good for 5lbs. Have a 294 going together with a Magnason blower and a strapped center main, so we'll find out.
How do you properly install a strap i have one with no instructions. Thanks
lonewolf is offline   Reply With Quote
Old 02-09-2015, 08:17 AM   #9
hotrodcbx
Member
 
Join Date: Jul 2010
Posts: 66
Default Re: Blower motor center main cap

I have a 286" blown flathead running 5 Lb boost built by MCF. His main cap was unique as he incorporated a flat surfaced, pivoting cap on the end of the bolt and also machined a flat spot on main bearing cap. This eliminates any "point loads" on the bearing cap and ensures the pivoting cap on the bolt seats flat on the machined surface. The engine has 25,000 miles now with no problems.
hotrodcbx is offline   Reply With Quote
Old 02-09-2015, 08:25 AM   #10
Tim Ayers
Senior Member
 
Join Date: May 2010
Location: NJ
Posts: 3,033
Default Re: Blower motor center main cap

Quote:
Originally Posted by hotrodcbx View Post
I have a 286" blown flathead running 5 Lb boost built by MCF. His main cap was unique as he incorporated a flat surfaced, pivoting cap on the end of the bolt and also machined a flat spot on main bearing cap. This eliminates any "point loads" on the bearing cap and ensures the pivoting cap on the bolt seats flat on the machined surface. The engine has 25,000 miles now with no problems.
A little off topic, but what ever happened to Mark Kirby? He certainly had some good ideas and had some momentum going with his Motor City Flathead.
Tim Ayers is offline   Reply With Quote
Old 02-09-2015, 10:24 AM   #11
GOSFAST
Senior Member
 
GOSFAST's Avatar
 
Join Date: May 2010
Location: Long Island, NY
Posts: 932
Default Re: Blower motor center main cap

Just a tip, we were never comfortable with that main strap setup. The center main section of these blocks is an extremely weak area. It doesn't take much to literally rip it out of the casting. If you examine the block you will see what I'm saying.

It is already tensed up by the main bolts/studs. It sees much of the internal stresses of the rotating ass'y. While the 4 center cylinders are in the firing cycle the loads are extremely high on that main, moreso when it is on a blown platform!

This "strap-the-caps" deal was a fairly common procedure years ago on the Chev's also, never agreed with it back then on those either.

The best way to add add'l support to that entire area is a "girdle" that straddles the center cap and ties the block together at the pan rails. We've done many this way, unfortunately I have no more of these girdles in inventory. If you talk to your builder he MAY be tempted to give it a try, making it from scratch?? It is a little time-consuming but not that difficult, it could be made on a conventional Bridgeport!

While we were using these, the way we programmed the part, it wasn't necessary to either line-bore OR line-hone, we made it fit minus both these procedures. Worked really well.

(Add) It also allowed the stock pans to remain, no pan modifications at all.

Thanks, Gary in N.Y.

P.S. Here's a shot of the pattern only, it is as thick/wide as the center cap and the side bolts did not hit any water! It was a nice setup at the time for us. I had made about 20 of them, used most, eventually sold the others.
Attached Images
File Type: jpg Flathead Main Girdle Pattern.JPG (25.2 KB, 130 views)
GOSFAST is offline   Reply With Quote
Old 02-09-2015, 10:35 AM   #12
Tim Ayers
Senior Member
 
Join Date: May 2010
Location: NJ
Posts: 3,033
Default Re: Blower motor center main cap

Quote:
Originally Posted by GOSFAST View Post
Just a tip, we were never comfortable with that main strap setup. The center main section of these blocks is an extremely weak area. It doesn't take much to literally rip it out of the casting. If you examine the block you will see what I'm saying.

It is already tensed up by the main bolts/studs. It sees much of the internal stresses of the rotating ass'y. While the 4 center cylinders are in the firing cycle the loads are extremely high on that main, moreso when it is on a blown platform!

This "strap-the-caps" deal was a fairly common procedure years ago on the Chev's also, never agreed with it back then on those either.

The best way to add add'l support to that entire area is a "girdle" that straddles the center cap and ties the block together at the pan rails. We've done many this way, unfortunately I have no more of these girdles in inventory. If you talk to your builder he MAY be tempted to give it a try, making it from scratch?? It is a little time-consuming but not that difficult, it could be made on a conventional Bridgeport!

While we were using these, the way we programmed the part, it wasn't necessary to either line-bore OR line-hone, we made it fit minus both these procedures. Worked really well.

(Add) It also allowed the stock pans to remain, no pan modifications at all.

Thanks, Gary in N.Y.

P.S. Here's a shot of the pattern only, it is as thick/wide as the center cap and the side bolts did not hit any water! It was a nice setup at the time for us. I had made about 20 of them, used most, eventually sold the others.

Hi Gary:

Seems like a well thought out piece. Curious, why did you stop and would you ever consider making more?

Thanks,

Tim
Tim Ayers is offline   Reply With Quote
Old 02-09-2015, 10:42 AM   #13
outlaw
Senior Member
 
Join Date: May 2010
Location: Eagle River,Alaska
Posts: 287
Thumbs up Re: Blower motor center main cap

Quote:
Originally Posted by GOSFAST View Post
Just a tip, we were never comfortable with that main strap setup. The center main section of these blocks is an extremely weak area. It doesn't take much to literally rip it out of the casting. If you examine the block you will see what I'm saying.

It is already tensed up by the main bolts/studs. It sees much of the internal stresses of the rotating ass'y. While the 4 center cylinders are in the firing cycle the loads are extremely high on that main, moreso when it is on a blown platform!

This "strap-the-caps" deal was a fairly common procedure years ago on the Chev's also, never agreed with it back then on those either.

The best way to add add'l support to that entire area is a "girdle" that straddles the center cap and ties the block together at the pan rails. We've done many this way, unfortunately I have no more of these girdles in inventory. If you talk to your builder he MAY be tempted to give it a try, making it from scratch?? It is a little time-consuming but not that difficult, it could be made on a conventional Bridgeport!

While we were using these, the way we programmed the part, it wasn't necessary to either line-bore OR line-hone, we made it fit minus both these procedures. Worked really well.

(Add) It also allowed the stock pans to remain, no pan modifications at all.

Thanks, Gary in N.Y.

P.S. Here's a shot of the pattern only, it is as thick/wide as the center cap and the side bolts did not hit any water! It was a nice setup at the time for us. I had made about 20 of them, used most, eventually sold the others.
I would be interested in a couple of these also. Bill
outlaw is offline   Reply With Quote
Old 02-09-2015, 01:41 PM   #14
scooder
Senior Member
 
Join Date: Jul 2010
Posts: 2,573
Default Re: Blower motor center main cap

Garry, does your girdle fit over the stock main cap?
Martin.
scooder is offline   Reply With Quote
Old 02-10-2015, 05:42 AM   #15
JWL
Senior Member
 
Join Date: May 2010
Location: Fitzgerald, Georgia
Posts: 1,950
Default Re: Blower motor center main cap

Another bad idea. The center main web CAN break out of the block. So, let us drill and tap more holes in it to help that process along.

Of the commercially available systems only that which requires extensive pan modification(like King's) and bolts to most of the pan rail length could be considered an improvement in rigidity and cycle resistance.
JWL is offline   Reply With Quote
Old 02-10-2015, 02:09 PM   #16
Pete
Senior Member
 
Pete's Avatar
 
Join Date: May 2010
Location: Wa.
Posts: 3,520
Default Re: Blower motor center main cap

Quote:
Originally Posted by JWL View Post
Another bad idea. The center main web CAN break out of the block. So, let us drill and tap more holes in it to help that process along.

Of the commercially available systems only that which requires extensive pan modification(like King's) and bolts to most of the pan rail length could be considered an improvement in rigidity and cycle resistance.
Amen.
Pete is online now   Reply With Quote
Old 01-10-2016, 10:58 AM   #17
saltracer
Member
 
Join Date: May 2014
Location: Lafayette, La.
Posts: 74
Default Re: Blower motor center main cap

had this made up by a local CNC shop.
saltracer is offline   Reply With Quote
Old 01-10-2016, 11:23 AM   #18
outlaw
Senior Member
 
Join Date: May 2010
Location: Eagle River,Alaska
Posts: 287
Question Re: Blower motor center main cap

Quote:
Originally Posted by saltracer View Post
had this made up by a local CNC shop.
Saltracer, Courious as to what that girdle cost? Bill
outlaw is offline   Reply With Quote
Old 01-10-2016, 11:42 AM   #19
VeryTangled
Senior Member
 
VeryTangled's Avatar
 
Join Date: May 2010
Location: (Not far enough...) Outside of DC
Posts: 2,595
Default Re: Blower motor center main cap

Quote:
Originally Posted by outlaw View Post
Saltracer, Courious as to what that girdle cost? Bill
Hi Everyone, Can I add some questions?

What kind of oil pan would that use? How would it attach?

Of course, that girdle stays on there when the engine is running, right? My mind is having a hard time turning that picture into a running engine.
__________________
-Jeff

Sorry I'm such a pill, but why not support the Early Ford V-8 Foundation Museum?

My avatar courtesy of 41ford1. Pic is him and Ol' Ron.
VeryTangled is offline   Reply With Quote
Old 01-10-2016, 11:56 AM   #20
outlaw
Senior Member
 
Join Date: May 2010
Location: Eagle River,Alaska
Posts: 287
Default Re: Blower motor center main cap

Quote:
Originally Posted by VeryTangled View Post
Hi Everyone, Can I add some questions?

What kind of oil pan would that use? How would it attach?

Of course, that girdle stays on there when the engine is running, right? My mind is having a hard time turning that picture into a running engine.
Yes the girdle stays there. You have to modify the oil pan. I have a friend here that did this with a girdle he bought when King was making them. On his though I seem to remember the girdle came drilled & tapped for the oil pan holes
outlaw is offline   Reply With Quote
Old 01-10-2016, 12:15 PM   #21
saltracer
Member
 
Join Date: May 2014
Location: Lafayette, La.
Posts: 74
Default Re: Blower motor center main cap

Quote:
Originally Posted by outlaw View Post
Yes the girdle stays there. You have to modify the oil pan. I have a friend here that did this with a girdle he bought when King was making them. On his though I seem to remember the girdle came drilled & tapped for the oil pan holes
using the previous oil pan screw holes is probably the way to go and if we make another we will probably change the design.

as far as cost, I do CNC machine repair for them and they do machine work for me (basically), so I would have to ask if they would like to reproduce the setup and how much. I can tell you they are not very busy.
saltracer is offline   Reply With Quote
Old 01-10-2016, 12:15 PM   #22
sidevalve8ba
Senior Member
 
sidevalve8ba's Avatar
 
Join Date: May 2013
Location: Harrisonburg, VA
Posts: 659
Default Re: Blower motor center main cap

Quote:
Originally Posted by JWL View Post
Another bad idea. The center main web CAN break out of the block. So, let us drill and tap more holes in it to help that process along.

Of the commercially available systems only that which requires extensive pan modification(like King's) and bolts to most of the pan rail length could be considered an improvement in rigidity and cycle resistance.
JWL, do you mean something like this?

http://flatheadjack.com/119.html
sidevalve8ba is offline   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 01-10-2016, 12:46 PM   #23
Ol' Ron
Senior Member
 
Ol' Ron's Avatar
 
Join Date: May 2010
Location: Chester Vt
Posts: 7,084
Default Re: Blower motor center main cap

Well the 294 produced 235HP @4500 RPM (Red Line) This has a strap on the center main. I believe this belongs in the application area. Running allot of boost might change that. What surprised me was the 290 foot of torque at 3000 RPM, That's allot of torque. Makes you think???? Nice street engine.
Ol' Ron is offline   Reply With Quote
Old 01-10-2016, 03:20 PM   #24
Walt Dupont--Me.
Senior Member
 
Walt Dupont--Me.'s Avatar
 
Join Date: May 2010
Location: Gardiner Me.
Posts: 4,200
Default Re: Blower motor center main cap

My 286 in my dragster, I made a strap for center main 1/2in. steel, drilled and tapped a 3/8 threaded hole in the center and screwed a grade 8 bolt and lock nut and tightened it down. Run it 3 years, red line 5000 through the traps every run. Broke the drive shaft at the tree, checked the recall on the tach back in the pits, turned 7000 rpm before my boy got his foot off the peddle. Still runs like a clock, strikes every hour. lol Walt
Walt Dupont--Me. is offline   Reply With Quote
Old 01-10-2016, 03:47 PM   #25
Bluebell
Senior Member
 
Join Date: Nov 2012
Location: Tauranga, New Zealand
Posts: 720
Default Re: Blower motor center main cap

I am totally ignorant of the dynamics involved,and never been involved in any of this sort of development, but my immediate thought on looking at this was "why not a full girdle incorporating all three bearing caps, that lends itself to a flat bolt on sump surface.
Bluebell is offline   Reply With Quote
Old 01-10-2016, 03:55 PM   #26
Pete
Senior Member
 
Pete's Avatar
 
Join Date: May 2010
Location: Wa.
Posts: 3,520
Default Re: Blower motor center main cap

Quote:
Originally Posted by Bluebell View Post
I am totally ignorant of the dynamics involved,and never been involved in any of this sort of development, but my immediate thought on looking at this was "why not a full girdle incorporating all three bearing caps, that lends itself to a flat bolt on sump surface.
Even with a much simpler and cheaper but similar design girdle, the block will stand way more horsepower than it is capable of producing blown and on nitro.
Pete is online now   Reply With Quote
Old 01-10-2016, 04:02 PM   #27
Bluebell
Senior Member
 
Join Date: Nov 2012
Location: Tauranga, New Zealand
Posts: 720
Default Re: Blower motor center main cap

I'm a learner. Thanks Pete.
Bluebell is offline   Reply With Quote
Old 01-10-2016, 06:39 PM   #28
flatrod
Senior Member
 
flatrod's Avatar
 
Join Date: Dec 2012
Location: Anchorage Alaska
Posts: 173
Default Re: Blower motor center main cap

Bill, the side rails were not drilled and taped. I did that when I made the pan. It uses the original pan bolts are used to hold the sides down, but were brought up to 3/8 in the block. Then the sides were drill for the pan. Maybe Jim has pictures.
We did all the girdle stuff because I am hoping to make 12 pounds of boost with a 471.

Quote:
Originally Posted by outlaw View Post
Yes the girdle stays there. You have to modify the oil pan. I have a friend here that did this with a girdle he bought when King was making them. On his though I seem to remember the girdle came drilled & tapped for the oil pan holes
flatrod is offline   Reply With Quote
Old 01-10-2016, 06:47 PM   #29
Ol' Ron
Senior Member
 
Ol' Ron's Avatar
 
Join Date: May 2010
Location: Chester Vt
Posts: 7,084
Default Re: Blower motor center main cap

The block is very thin along the rails
Ol' Ron is offline   Reply With Quote
Old 01-11-2016, 01:02 AM   #30
outlaw
Senior Member
 
Join Date: May 2010
Location: Eagle River,Alaska
Posts: 287
Smile Re: Blower motor center main cap

Quote:
Originally Posted by flatrod View Post
Bill, the side rails were not drilled and taped. I did that when I made the pan. It uses the original pan bolts are used to hold the sides down, but were brought up to 3/8 in the block. Then the sides were drill for the pan. Maybe Jim has pictures.
We did all the girdle stuff because I am hoping to make 12 pounds of boost with a 471.
Dennis, Thanks I guess that Jim had shown it to me after you had finished the pan mods. Bill

Last edited by outlaw; 01-11-2016 at 01:08 AM.
outlaw is offline   Reply With Quote
Old 01-11-2016, 01:05 AM   #31
outlaw
Senior Member
 
Join Date: May 2010
Location: Eagle River,Alaska
Posts: 287
Default Re: Blower motor center main cap

Quote:
Originally Posted by saltracer View Post
using the previous oil pan screw holes is probably the way to go and if we make another we will probably change the design.

as far as cost, I do CNC machine repair for them and they do machine work for me (basically), so I would have to ask if they would like to reproduce the setup and how much. I can tell you they are not very busy.
Saltracer, I was just courious at this time. I have to finish the model A I'm trying to build first, then my next project is a 36 coupe & I've got a 4-71 for it. Bill
outlaw is offline   Reply With Quote
Old 01-11-2016, 12:48 PM   #32
Jason in TX
Senior Member
 
Jason in TX's Avatar
 
Join Date: May 2010
Location: ⓉⒺXⒶⓈ
Posts: 2,038
Default Re: Blower motor center main cap

At The Race of Gentlemen, Brian Bass brought his 32 roadster with a mostly stock flathead. A week before the race, he obtained this new H&H Scot blower and decided to bolt it on before the race. It sure woke the engine up.

On about his 3rd race, I was in the other lane and near the end of the run, we could both hear a loud *POP* as if the car transmission popped out of second gear. However, he didn't remember it popping out of gear. He drove it back to the pits, idled the engine, revved it and heard no knocking or any unusual noises.

He went back out on the track and raced 3 more times HARD and winning, and then drove the car back to his trailer about a mile away. When loading the car, he noticed dents in the oil pan.

upon getting back to Dallas and dropping the pan, he found the main cap had sheered both main studs. Very lucky he didn't grenade the engine, but also an interesting occurance.

Anyways, The supercharger can put enough force to blow the main cap!



__________________
--------------
Drive it like you know how to fix it!
DMAFC / OILERS CC-MC
Jason in TX is offline   Reply With Quote
Old 01-11-2016, 01:24 PM   #33
Bored&Stroked
Senior Member
 
Bored&Stroked's Avatar
 
Join Date: Jan 2011
Location: Central Ohio
Posts: 2,267
Default Re: Blower motor center main cap

I'd say that he is about as lucky as they come - can't imagine that the crank didn't let go! I'll bet his oil pressure had dropped off quite a bit?

I always replace the stock studs with ARPs. Maybe they help . . . maybe they don't, but in the grand scheme of things - not too expensive of an insurance plan (even for stock caps).
Bored&Stroked is offline   Reply With Quote
Old 01-11-2016, 01:48 PM   #34
Fordestes
Senior Member
 
Join Date: May 2010
Posts: 689
Default Re: Blower motor center main cap

Glad to see some info on blower engines, I have a set up from Mike Davidson Flatattack, it uses the billet caps and a re-enforcing plate, After seeing the broken bolts I am going to get the A.R.P studs, the kit has grade 5 bolts, I think the grade 5s will be a little too weak after going to all the expense to use this set up I cant imagine why one would use such soft bolts? They came with the kit. What is the deal about installing studs , I have heard a lot of people set and argue what is the correct way to install studs in an engine block ,some say tighten to torque spec. and some say don't tighten to spec. seems to me they will either be tight enough or not torqued and too loose and will come out. which is it?
fordestes
Fordestes is offline   Reply With Quote
Old 01-11-2016, 02:01 PM   #35
Tim Ayers
Senior Member
 
Join Date: May 2010
Location: NJ
Posts: 3,033
Default Re: Blower motor center main cap

Quote:
Originally Posted by Bored&Stroked View Post
I'd say that he is about as lucky as they come - can't imagine that the crank didn't let go! I'll bet his oil pressure had dropped off quite a bit?

I always replace the stock studs with ARPs. Maybe they help . . . maybe they don't, but in the grand scheme of things - not too expensive of an insurance plan (even for stock caps).
Dale:

You said it. I can't believe the entire package didn't let go. That's pretty amazing.

Tim
Tim Ayers is offline   Reply With Quote
Old 01-11-2016, 02:09 PM   #36
Pete
Senior Member
 
Pete's Avatar
 
Join Date: May 2010
Location: Wa.
Posts: 3,520
Default Re: Blower motor center main cap

Quote:
Originally Posted by Fordestes View Post
Glad to see some info on blower engines, I have a set up from Mike Davidson Flatattack, it uses the billet caps and a re-enforcing plate, After seeing the broken bolts I am going to get the A.R.P studs, the kit has grade 5 bolts, I think the grade 5s will be a little too weak after going to all the expense to use this set up I cant imagine why one would use such soft bolts? They came with the kit. What is the deal about installing studs , I have heard a lot of people set and argue what is the correct way to install studs in an engine block ,some say tighten to torque spec. and some say don't tighten to spec. seems to me they will either be tight enough or not torqued and too loose and will come out. which is it?
fordestes
I screw them in by hand with Loctite on the threads and 1/2 turn off the bottom. I let them sit overnight before proceeding.
Pete is online now   Reply With Quote
Old 01-11-2016, 02:33 PM   #37
flatheadmurre
Senior Member
 
flatheadmurre's Avatar
 
Join Date: Apr 2015
Location: Sweden
Posts: 2,488
Default Re: Blower motor center main cap

Quote:
Originally Posted by Pete View Post
I screw them in by hand with Loctite on the threads and 1/2 turn off the bottom. I let them sit overnight before proceeding.
I was told the threads should be loaded before it sets.
Other wise when you tighten it up the loctite starts to move if you go over the holding point.
flatheadmurre is offline   Reply With Quote
Old 01-11-2016, 04:48 PM   #38
flatrod
Senior Member
 
flatrod's Avatar
 
Join Date: Dec 2012
Location: Anchorage Alaska
Posts: 173
Default Re: Blower motor center main cap

I tighten studs in by hand. If its a take-a-part engine, then I usually lock tight them in. If you try to torque them in to a hole that is open, then you are forcing the shank of the stud into the threads. All you will do is screw up the threads.



Quote:
Originally Posted by Fordestes View Post
What is the deal about installing studs , I have heard a lot of people set and argue what is the correct way to install studs in an engine block ,some say tighten to torque spec. and some say don't tighten to spec. seems to me they will either be tight enough or not torqued and too loose and will come out. which is it?
fordestes
flatrod is offline   Reply With Quote
Old 01-11-2016, 05:00 PM   #39
Pete
Senior Member
 
Pete's Avatar
 
Join Date: May 2010
Location: Wa.
Posts: 3,520
Default Re: Blower motor center main cap

Quote:
Originally Posted by flatheadmurre View Post
I was told the threads should be loaded before it sets.
Other wise when you tighten it up the loctite starts to move if you go over the holding point.
The stud never moves. It is a coarse thread.
I didn't invent the idea. The guys that teach this stuff figured it out by math and then lab trials.
I know a lot of people that build many different kinds of mechanical gizmos and they all do it this way.
Pete is online now   Reply With Quote
Old 01-11-2016, 05:18 PM   #40
flatheadmurre
Senior Member
 
flatheadmurre's Avatar
 
Join Date: Apr 2015
Location: Sweden
Posts: 2,488
Default Re: Blower motor center main cap

I installed large studs and it was very specific installed heights and we had spacers on and preloaded every bolt to specs.
And this was Loctites products and their techs teaching us.
But perhaps it matters more when things are larger in diam.
flatheadmurre is offline   Reply With Quote
Old 01-11-2016, 06:11 PM   #41
Jason in TX
Senior Member
 
Jason in TX's Avatar
 
Join Date: May 2010
Location: ⓉⒺXⒶⓈ
Posts: 2,038
Default Re: Blower motor center main cap

Since a few people said they are learning about this, and pictures speak a thousand words, Here are a few pictures of "the strap"

It's a piece of I beam, with some spacers on the main cap bolts and a set screw/bolt in the center designed to push back on the center. They have the reputation of being a cap splitter, with people feeling all that force on that center bolt can act as a chisel and break the cap in the center.

They are installed with the center bolt thumb tight and then locked in that place. It doesn't have force pushing up on the cap. Just keeping it from flexing down.




This is the version that speedway sells:

__________________
--------------
Drive it like you know how to fix it!
DMAFC / OILERS CC-MC
Jason in TX is offline   Reply With Quote
Old 01-11-2016, 09:12 PM   #42
Pete
Senior Member
 
Pete's Avatar
 
Join Date: May 2010
Location: Wa.
Posts: 3,520
Default Re: Blower motor center main cap

Quote:
Originally Posted by flatheadmurre View Post
I installed large studs and it was very specific installed heights and we had spacers on and preloaded every bolt to specs.
And this was Loctites products and their techs teaching us.
But perhaps it matters more when things are larger in diam.
Different methods work for different applications.
For studs in cast iron, which we are talking about here, if you bottom them even by hand, there is a REAL possibility the deck can be pulled up around the stud or the bottom of a blank hole punched out.
Pete is online now   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 01-11-2016, 09:32 PM   #43
Fordestes
Senior Member
 
Join Date: May 2010
Posts: 689
Default Re: Blower motor center main cap

so I put the studs in with loctite and tighten down to bottom by hand and then back the stud out by 1/2 turn and let set over night. would it be acceptable to put a main cap on after they are set to put a little tension on the threads so the Loctite can set as if it were in the installed position and the Loctite get into the places it wouldn't normally go without tension on the threads as Pete described and let set overnight, would green Loctite be a good thread compound to use after cleaning out the threads with acetone to get rid of all the oil and grease?
Thanks for clearing that up for us.
Fordestes
Fordestes is offline   Reply With Quote
Old 01-12-2016, 02:22 AM   #44
Pete
Senior Member
 
Pete's Avatar
 
Join Date: May 2010
Location: Wa.
Posts: 3,520
Default Re: Blower motor center main cap

Quote:
Originally Posted by Fordestes View Post
so I put the studs in with loctite and tighten down to bottom by hand and then back the stud out by 1/2 turn and let set over night. would it be acceptable to put a main cap on after they are set to put a little tension on the threads so the Loctite can set as if it were in the installed position and the Loctite get into the places it wouldn't normally go without tension on the threads as Pete described and let set overnight, would green Loctite be a good thread compound to use after cleaning out the threads with acetone to get rid of all the oil and grease?
Thanks for clearing that up for us.
Fordestes
I didn't mention it but it is a very good idea to clean the area with acetone or tri chlor before doing Loctite.
They tell you that in the instructions.
It wouldn't hurt to put the cap on as you describe, overnight.
Pete is online now   Reply With Quote
Old 01-12-2016, 04:32 AM   #45
flatheadmurre
Senior Member
 
flatheadmurre's Avatar
 
Join Date: Apr 2015
Location: Sweden
Posts: 2,488
Default Re: Blower motor center main cap

Quote:
Originally Posted by Pete View Post
Different methods work for different applications.
For studs in cast iron, which we are talking about here, if you bottom them even by hand, there is a REAL possibility the deck can be pulled up around the stud or the bottom of a blank hole punched out.
Never said i installed them torqued into the block.
Just that i was told they should be loaded so the loctite doesnt get between the surfaces of the thread distributing the load when torqued later.
So installing the cap and preloading the stud while setting would be one way of doing it.
Enough of that im probably just overcomplicating things here...
flatheadmurre is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Sponsored Links (Register now to hide all advertisements)


All times are GMT -5. The time now is 09:59 PM.