Fan blade clearance

Here are some pictures of the problem and then of the car I'm working on. rsz_101010_069.jpg

rsz_various_2011_035.jpg

rsz_various_2011_047.jpg

Thanks for the help with the pictures. The resize link you sent was great!
 
How much distance do you have from the water pump shaft to the radiator?

All original parts on my 28 and it has 3/4 to 1" from the shaft end to the radiator core.
 
I will check the size of the springs and also the distance between the water pump shaft and the radiator core. I have over an inch at this point I'm sure.
 
Well I took apart the front motor mount (no easy task) and the springs checked out ok (1-9/16"). When I put it back together I noticed that the bottom of the crank pulley is hitting the bottom of the motor mount. I think the engine is sitting back to far but I don't know how that could happen. Any suggestions would be appreciated.
Thanks
 
I think everyone has suggested everything except the radiator core height. If the radiator core has been changed, it is possible the shop installed a core slightly shorter that the original core. Was there any fit up problems installing the radiator shell?
 
rmyers said:
Where do I find the frame number? I'm not sure about the return tubes, where are they located?
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The top radiator is the only pipe with a clearance problem, isn't it?

The return pipe is the bottom radiator pipe and 28-9 has the bend off center, while the bend is in the middle for the 1930-1 pipes.
 
I checked with Snyders about the radiator height, because that is what I thought of also but it is the same height. Actually its a little taller. The top pipe is in the center and the bottom pipe is offset on the drivers side and a little angled to that side also. The top pipe is the only one with clearance issues, except now with the crank pulley hitting the front motor mount.
 
There are differences between a 28 and 30 crossmember no? I thought the 30-31 crossmember was lower where the radiator sits. I could see this causing the problem you have. 28-29 should be slightly raised where the pads sit while a 30-31 is indented.
 
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rmyers said:
Well I took apart the front motor mount (no easy task) and the springs checked out ok (1-9/16"). When I put it back together I noticed that the bottom of the crank pulley is hitting the bottom of the motor mount. I think the engine is sitting back to far but I don't know how that could happen. Any suggestions would be appreciated.
Thanks
Click to expand...

Some of the repro crankshaft pulleys are off a little. The popular vendor that I bought mine from listed two pulleys, one was USA, the other was foreign made but machined in the USA, if this sounds familiar. I bought the USA pulley. The spokes of the pulley was barely hitting the front motor mount yoke. The easiest fix was to remove the yoke and grind a bit off for clearance and that is what I did with good results. I only had to remove a small amount from the mount yoke and after repainting it you can't tell that any mod was made. That is not the only problem that I had with the pulley, I had to ream the pulley before it would even fit the crankshaft. If I had known what a piece of junk the pulley was I would have sent it back before going to all of the trouble. This was on one of my 1931 model A's

I had the problem with the fan like you mention on my sept. 29 strip down. I used a new Repro radiator of unknown manifacture. and a new aluminum two blade fan. I had two of the rubber shims under each side of the radiator and if I had put more I would have needed to use longer bolts. I noticed that the fan was close to the upper radiator outlet but hoped it would get by. When I cranked the engine I could hear a noise when I slightly reved it. After a close look I could see marks where the fan was hitting the edge of the upper hose. The problem was with the position of the upper neck of the aftermarket radiator. Rather than running the risk of ruining an otherwise good radiator by trying to remove and resolder the upper neck I chose a different route. I figured the best way to go would be remove the fan and shorten the blades. I removed 3/4 inch from each blade so I would have room to spare. This worked quiet well. I have only heard of this problem with the 28-29 radiators.
 
I will look at the crossmember to see if it is indented or not but its kind of looking like I'm going to have to remove some metal off the fan blades. I have to figure out the motor mount thing first now before I go any further. I don't think it was hitting when I installed the engine so I'm not sure what changed but I will take it back apart and look again.
 
I agree with some of the above comments except for changing to a smaller fan. Make sure the front of the engine is low enough to line up with the crank hole. If it's too high loosen the rear mounts and slide a jack under the transmission and tighten the front motor mount nut until you get perfect alignment with the crank then retighten the rear mounts and remove the jack. Check that you have the proper head neck casting for 28/29. I had that problem with a 29 and had to tighten down the front mount quite a bit. Another point is repro radiators are not made all the same and the upper pipe can be at the wrong angle or position.
 
There is an interesting article about fans in the how to restore your model A second edition green cover book. The artical is by Ed Rossig starting on page 99. Tests are made with the original fan, the 4 blade truck fan and the original fan with 2 inches removed from each blade. there was also a test with NO fan. The no fan test was done on a 92 degree day, it was found that water temperature remained at 170 degrees while maintaining a speed of 50 miles per hour for two hours. Shortening the fan blades reduces vibration and the risk of failure. This is a very informative read!!!
 
I just wanted to let everyone know that I ended up adding 2 additional pieces of rubber and that made the clearance perfect and also brought the hood into better alignment. I know that is probably not the right answer for the problem but it works for me. Thanks to everyone for their input, this is a great site for information. I'm a first timer and I have a lot to learn. For as simple as these cars are they sure are tough to work on if you don't know what you're doing.
Thanks again!
 
As I write this, the Model A Radiator Mount Police are on their way to Ohio.................. Glad you were able to resolve your problem and letting us know the solutioin.
Paul in CT
 
As far as I know, (which is not much about A's) I think the 28 had a different cross member. Also the 29 had a different one and the 30/31's had a different one again.

I think this is correct based on what I have learned from people on this site that know more about this thing than I do. I need another front cross member for my 29 and asked on this site about what to get and received some very valuable info.
 
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