The Ford Barn

Mart · 10-04-2022, 02:47 PM

Hello and welcome to Part 15 of my Volvo transmission swap. In this video I wind the clock back to after the disastrous first start. Watching in retrospect I can see what the problem was but I didn't realise it at the time and ploughed on blindly. If you don't know what happened watch part 13 where I explain what went on. In that video I said I would flesh out the story. Well, this video continues the fuller version of the tale

https://youtu.be/U-8TN3wWikQ

Bored&Stroked · 10-04-2022, 03:52 PM

Hey Mart, my guess is that there was not enough lubrication and/or clearance on the rear thrust surface. When you press the clutch in, all the load goes to the rear main thrust - and it burned.

Was this the engine with the very-low oil pressure? You should never have less than 10 - 15 lbs at idle (I know I never have with any engine) - more like 20 - 25 even when really hot. If this is the case, then when you're idling the engine at a stop (with no oil pressure), then the rear thrust isn't getting oil, so the lack of lubrication could easily cause the bearing to heat up, burn and then be wiped out.

Another cause can be too tight of a thrust clearance - I like to have about .005 to .006 or so. If you tightened it up too much with a shim in the front of the rear shell, this might also be a culprit. Did you plastigauge the mains to see what clearance you had in the rear? I like to have .0025 to .00275 in the rear - especially if I'm going to be racing it as the rear main gets hot from the clutch, so the clearances will get tighter and this can cause lubrication issues. The rear main is the one that will cause the most issues.

A little "trick" I do is chamfer the edge of the rear main bearing a bit - to help get some oil to the thrust.

Here is an example of the 284 CI engine in my 32 CAB:

MBRear chamfer.jpg

RB · 10-04-2022, 09:37 PM

Good observation bored & stroked, would be great to have additional serious racing guys chime in particularly those exposed to similar issues.... more info the better.

cadillac512 · 10-04-2022, 10:11 PM

I believe in a previous video (maybe #13?) Mart explained that a mistake was made in the pilot bearing area that allowed the transmission input shaft to overload the crankshaft thrust bearing resulting in the destruction of thrust surfaces. That would do it...thrust bearings do not like constant loading.

Terry

Bored&Stroked · 10-05-2022, 05:26 AM

Quote:

Originally Posted by cadillac512

I believe in a previous video (maybe #13?) Mart explained that a mistake was made in the pilot bearing area that allowed the transmission input shaft to overload the crankshaft thrust bearing resulting in the destruction of thrust surfaces. That would do it...thrust bearings do not like constant loading.

Terry

I didn't see that one and if it had constant loading, that would be bad - and would probably burn the thrust as this one shows.

Mart · 10-05-2022, 07:20 AM

Sponsored Links (Register now to hide all advertisements)

Hey, sorry for all the head scratching and I appreciate all the excellent advice given. The videos are showing in retrospect what happened after the first run with the Volvo conversion. Things moved at such a pace and with the GOW! event at Prescott looming I wasn't able to edit up the videos at the time. I am currently editing the footage which reveals the smoking gun. The adaptor bush I made for the input shaft had a too thick shoulder on it which put a constant heavy load on the crank, via the pilot bearing. This trashed the crank and rear main in my race motor. I fitted an old stock motor to allow me to run the car at the event. It is the stock motor that has the low oil pressure problem and I showed some of that in a video.
I will put out a video on Friday showing the part that caused the issue. This will be another retrospective video so I will have to state that clearly.

Thanks for all the interest.

Mart.

RB · 10-05-2022, 08:30 AM

Really unfortunate but no hill for a climber such as you Mart, you have your fair share of patience, in & out with the engine & engineering along the way, just a mere stubbed toe on occasion nothing we know you won't overcome.

RB · 10-08-2022, 10:15 AM

Good sleuthing on Mart's part & those commenting as well, something to keep in mind when installing a flathead where transmissions other than the norm have been swapped. Great drivability updates thoroughly enjoyed we should all be grateful of the time & effort put forth. Thanks Mart .

10-04-2022, 03:52 PM	#2
Bored&Stroked Senior Member Join Date: Jan 2011 Location: Central Ohio Posts: 5,068	Re: Part 15: 4spd OD in a 1932 Ford. Simple tasks lead to epic fail discovery Hey Mart, my guess is that there was not enough lubrication and/or clearance on the rear thrust surface. When you press the clutch in, all the load goes to the rear main thrust - and it burned. Was this the engine with the very-low oil pressure? You should never have less than 10 - 15 lbs at idle (I know I never have with any engine) - more like 20 - 25 even when really hot. If this is the case, then when you're idling the engine at a stop (with no oil pressure), then the rear thrust isn't getting oil, so the lack of lubrication could easily cause the bearing to heat up, burn and then be wiped out. Another cause can be too tight of a thrust clearance - I like to have about .005 to .006 or so. If you tightened it up too much with a shim in the front of the rear shell, this might also be a culprit. Did you plastigauge the mains to see what clearance you had in the rear? I like to have .0025 to .00275 in the rear - especially if I'm going to be racing it as the rear main gets hot from the clutch, so the clearances will get tighter and this can cause lubrication issues. The rear main is the one that will cause the most issues. A little "trick" I do is chamfer the edge of the rear main bearing a bit - to help get some oil to the thrust. Here is an example of the 284 CI engine in my 32 CAB: MBRear chamfer.jpg Last edited by Bored&Stroked; 10-04-2022 at 04:09 PM.

10-04-2022, 09:37 PM	#3
RB Senior Member Join Date: May 2010 Location: papillion nebraska Posts: 406	Re: Part 15: 4spd OD in a 1932 Ford. Simple tasks lead to epic fail discovery Good observation bored & stroked, would be great to have additional serious racing guys chime in particularly those exposed to similar issues.... more info the better.

10-04-2022, 10:11 PM	#4
cadillac512 Senior Member Join Date: Apr 2019 Location: Kansas Posts: 921	Re: Part 15: 4spd OD in a 1932 Ford. Simple tasks lead to epic fail discovery I believe in a previous video (maybe #13?) Mart explained that a mistake was made in the pilot bearing area that allowed the transmission input shaft to overload the crankshaft thrust bearing resulting in the destruction of thrust surfaces. That would do it...thrust bearings do not like constant loading. Terry __________________ "It don't take but country smarts to solve the problem" (Smokey Yunick) '41 Merc Town Sedan / 260" 8CM engine '66 Fairlane four door / "warmed up" 302

10-05-2022, 07:20 AM	#6
Mart Senior Member Join Date: May 2010 Location: Solihull, England. Posts: 8,755	Re: Part 15: 4spd OD in a 1932 Ford. Simple tasks lead to epic fail discovery Sponsored Links (Register now to hide all advertisements) Hey, sorry for all the head scratching and I appreciate all the excellent advice given. The videos are showing in retrospect what happened after the first run with the Volvo conversion. Things moved at such a pace and with the GOW! event at Prescott looming I wasn't able to edit up the videos at the time. I am currently editing the footage which reveals the smoking gun. The adaptor bush I made for the input shaft had a too thick shoulder on it which put a constant heavy load on the crank, via the pilot bearing. This trashed the crank and rear main in my race motor. I fitted an old stock motor to allow me to run the car at the event. It is the stock motor that has the low oil pressure problem and I showed some of that in a video. I will put out a video on Friday showing the part that caused the issue. This will be another retrospective video so I will have to state that clearly. Thanks for all the interest. Mart.

10-05-2022, 08:30 AM	#7
RB Senior Member Join Date: May 2010 Location: papillion nebraska Posts: 406	Re: Part 15: 4spd OD in a 1932 Ford. Simple tasks lead to epic fail discovery Really unfortunate but no hill for a climber such as you Mart, you have your fair share of patience, in & out with the engine & engineering along the way, just a mere stubbed toe on occasion nothing we know you won't overcome.

10-04-2022, 02:47 PM	#1
Mart Senior Member Join Date: May 2010 Location: Solihull, England. Posts: 8,755	Part 15: 4spd OD in a 1932 Ford. Simple tasks lead to epic fail discovery Hello and welcome to Part 15 of my Volvo transmission swap. In this video I wind the clock back to after the disastrous first start. Watching in retrospect I can see what the problem was but I didn't realise it at the time and ploughed on blindly. If you don't know what happened watch part 13 where I explain what went on. In that video I said I would flesh out the story. Well, this video continues the fuller version of the tale https://youtu.be/U-8TN3wWikQ

10-08-2022, 10:15 AM	#8
RB Senior Member Join Date: May 2010 Location: papillion nebraska Posts: 406	Re: Part 15: 4spd OD in a 1932 Ford. Simple tasks lead to epic fail discovery Good sleuthing on Mart's part & those commenting as well, something to keep in mind when installing a flathead where transmissions other than the norm have been swapped. Great drivability updates thoroughly enjoyed we should all be grateful of the time & effort put forth. Thanks Mart .