|
Sponsored Links (Register now to hide all advertisements) |
|
|
Thread Tools | Display Modes |
02-23-2019, 05:20 PM | #1 |
Senior Member
Join Date: Aug 2018
Location: Foley, Al
Posts: 142
|
After replacing with 2 bladed aluminum fan, engine noise abounds
I had a good original fan but after hearing so many people warn against them I purchased and installed a 2 blade aluminum cast fan. The instructions said that you may need to file some of the "nose" of the water pump if the cast fan rubs so I did that but just enough so it didn't rub.
After installing it, we took the model A to a couple events and the engine would occasionally develop a noisy clanging like sound. More often than not, quite noisy and sometimes barely audible. So I removed the fan belt today and the noise went away so I was able to cite that as the source of the noise. Then I wiggled the fan and it seems like excessive play. Now I'm not sure the best way to take that play out. Here's a video of me wiggling the fan blade (pretty amateur). https://youtu.be/_V-uWNBL8vw Any tips to help me figure this out would be appreciated. p.s. For those stuck in the cold weather, here's a picture of our truck today at an event in Pinellas county Florida
__________________
Jim |
02-23-2019, 05:48 PM | #2 |
Senior Member
Join Date: Jun 2014
Location: Melbourne, Australia
Posts: 7,496
|
Re: After replacing with 2 bladed aluminum fan, engine noise abounds
It looks to like you didn't tighten the fan onto the taper enough. There should be a steel washer between the fan and the but that holds it on. The washer is to prevent the nut chewing up the soft aluminium fanwhen you tighten it - that's how much you have to tighten it. Depending on how long it has been loose, you may have damaged the taper in the fan. I'd try tightening it and see if I could get it to run true again.
__________________
I'm part of the only ever generation with an analogue childhood and a digital adulthood. |
Sponsored Links (Register now to hide all advertisements) |
|
02-23-2019, 07:13 PM | #3 | |
Senior Member
Join Date: Aug 2018
Location: Foley, Al
Posts: 142
|
Re: After replacing with 2 bladed aluminum fan, engine noise abounds
Quote:
__________________
Jim |
|
02-23-2019, 07:57 PM | #4 |
Senior Member
Join Date: Apr 2013
Location: Northwest CT
Posts: 1,092
|
Re: After replacing with 2 bladed aluminum fan, engine noise abounds
There were also some repro water pump shafts that didn't have the correct taper and could cause a wobble. You said you replaced an original fan that didn't have this problem so it's probably not the shaft but it is some food for thought.
|
02-23-2019, 08:17 PM | #5 |
Senior Member
Join Date: Aug 2018
Location: Foley, Al
Posts: 142
|
Re: After replacing with 2 bladed aluminum fan, engine noise abounds
It's fixed ! Nice sounding engine again with no weird noises. I tried putting a steel washer on but then there just wasn't enough clearance to get the cotter key in. So plan B was to crank the nut down to tighten the fan as snug as possible and it worked.
The problem didn't start right away after installing the new fan blade so maybe it loosened up some after I started running it. And the nut probably should have been tightened more in the first place. I guess after breaking things over the years by over tightening I'm a bit more cautious as I get older. I can't put into words how much I enjoy ...no, LOVE ... working on the Model 'A'. A great sense of satisfaction when you repair something. And this forum is the best resource out there. I've learned a lot reading all the helpful posts you good people have posted. Thanks again,
__________________
Jim |
02-23-2019, 08:38 PM | #6 |
Senior Member
Join Date: Apr 2013
Location: Northwest CT
Posts: 1,092
|
Re: After replacing with 2 bladed aluminum fan, engine noise abounds
Sponsored Links (Register now to hide all advertisements)
|
02-23-2019, 09:36 PM | #7 |
Senior Member
Join Date: Feb 2011
Location: Lincoln, Nebraska
Posts: 1,909
|
Re: After replacing with 2 bladed aluminum fan, engine noise abounds
If you run across not being able to get a cotter key in again try filing a small amount off the bottom of the castle nut a little at a time.
__________________
Dave / Lincoln Nebraska |
02-23-2019, 10:53 PM | #8 |
Senior Member
Join Date: Dec 2011
Location: SW Idaho
Posts: 970
|
Re: After replacing with 2 bladed aluminum fan, engine noise abounds
Don't throw the key away and check the nut regular. Key should be in.
|
02-24-2019, 06:26 AM | #9 |
Senior Member
|
Re: After replacing with 2 bladed aluminum fan, engine noise abounds
If the tapers don't match, the belt load will cause wobble and tightening the nut is not the answer. Make sure they match.
|
02-24-2019, 06:50 AM | #10 | |
Senior Member
Join Date: Aug 2018
Location: Foley, Al
Posts: 142
|
Re: After replacing with 2 bladed aluminum fan, engine noise abounds
Quote:
btw Jack, I had an opportunity to pull out your book a few weeks ago "Get a Horse", on how to fix the Model A on the road. A few onlookers in the area had a good chuckle when they saw the name of the book. I'll be thinking of you Michiganders getting hit today with that "bomb cyclone" winter storm while I'm out taking my test drive
__________________
Jim |
|
02-24-2019, 10:04 AM | #11 |
Senior Member
Join Date: Oct 2010
Location: bozeman mt
Posts: 170
|
Re: After replacing with 2 bladed aluminum fan, engine noise abounds
if you have the wrong taper you can tighten it but it will get loose again even
with the cotter key installed. don't ask me howi know. |
02-24-2019, 10:47 AM | #12 |
Senior Member
Join Date: Jul 2010
Location: upstate NY near Mass border
Posts: 789
|
Re: After replacing with 2 bladed aluminum fan, engine noise abounds
So how do you tell if you have the wrong taper, what's the test? Jack
|
02-24-2019, 11:59 AM | #13 |
Senior Member
Join Date: May 2010
Location: So Cal
Posts: 8,753
|
Re: After replacing with 2 bladed aluminum fan, engine noise abounds
I like to put some lapping compound on the shaft, no key installed, then lap the
fan to the shaft a little. To check the fit put a little prussian blue on the shaft and slide the fan on then remove it and check the contact. |
02-24-2019, 01:19 PM | #14 |
Senior Member
Join Date: May 2010
Posts: 335
|
Re: After replacing with 2 bladed aluminum fan, engine noise abounds
Bob C has the answer. Magic marker on the shaft works too. Get the tapers to match before you crack the new fan or wallow out the fan taper.
|
02-24-2019, 04:15 PM | #15 |
Senior Member
|
Re: After replacing with 2 bladed aluminum fan, engine noise abounds
The belt load is offset from the bearing and puts a moment on the joint between the fan hub and shaft. Run your belt tension as low as you can. Put the fan on the shaft and try to wobble it. If it wobbles do the lapping compound trick. Must be no movement.
|
02-24-2019, 05:16 PM | #16 |
Senior Member
Join Date: Jun 2014
Location: Melbourne, Australia
Posts: 7,496
|
Re: After replacing with 2 bladed aluminum fan, engine noise abounds
I agree with this one completely. Many (most) people run the belt too tight. Mine is so loose, I can almost turn the belt with the motor stopped. I can easily turn the fan with only one finger, yet the alternator charges and the water pump pumps. The very design of a vee belt means that they tighten into the pulley as they drive. The more drive needed, the more they grip. Too tight only shortens the life of belt and bearings.
__________________
I'm part of the only ever generation with an analogue childhood and a digital adulthood. |
02-24-2019, 09:45 PM | #17 |
Senior Member
Join Date: May 2010
Location: Mpls, MN
Posts: 27,582
|
Re: After replacing with 2 bladed aluminum fan, engine noise abounds
For sure, the belt only needs to be tight enough so the fan and generator pulleys don't slip.
|
|
|
Sponsored Links (Register now to hide all advertisements) |
|