How far should I go with my '41 flathead
 

I need to replace the main seal on my 41 Ford Super Deluxe Convertible and will likely pull the engine to do that. If we do pull the engine, I'm wondering if if it makes any sense crack it open, inspect it and possibly do an overhaul or would I be better off to just leave it alone.

The car runs nice, but does run hot (which I know has a whole host of potential causes/remedies, which I'm working in parallel to resolve). I'm wondering (due to another forum I read awhile back) if there could be some reduced coolant flow due to sediment that has accumulated over 85 years (engine has not been touched to my knowledge).

What do you think? Worth poking a little further or let it be?

Thanks!

Sam

Re: How far should I go with my '41 flathead
 

It's all about the finances, IF you have the money to spend, now would be the time (and easiest) to do it..... have the block properly cleaned, magnafluxed and pressure tested......IF it checks out fine THEN have it properly checked and redone as needed!!!! You know 100% then what is left with your cooling issue!!!! AND you have many many years of carefree driving on a known GOOD engine!!

Re: How far should I go with my '41 flathead
 

I’m not sure if your engine has a rear seal . It could have a slinger . Unfortunately I can’t remember, even though I had a 41 engine apart last year . It stinks getting old . Better than the alternative.
I would look for a good running engine that would fit your car and then rebuild your original.
Sometimes a simple rebuild takes way longer than you anticipated . It’s much more fun driving your car than paying bills for it and not enjoying it .

Re: How far should I go with my '41 flathead
 

shinton >> I need to replace the main seal on my 41 Ford >>car runs nice,>>


How do you know it needs to be replaced? Try to describe how much you think it's leaking during & after a good run.

Re: How far should I go with my '41 flathead
 

Your 41 should have a rope type seal at both ends of the crank.

Re: How far should I go with my '41 flathead
 

Thought Ford used the slinger through 1942.

Re: How far should I go with my '41 flathead
 

Probably would be be a good thing to have it checked out, but be prepared for the cost associated with it as you might be going down the road of a partial rebuild.

Re: How far should I go with my '41 flathead
 

If the car really "runs nice", I'd replace the seal and leave the rest alone. I might not even replace the seal. You don't know what you might run into if you decide to open it up. If there's a problem (low compression, low oil pressure, coolant loss, or something like that), then go ahead. I would be afraid of a crack in the block that is currently not leaking being discovered. You really can't put it back together again, and rebuilding it with a known cracked block is not recommended. And then what if you can't find another block?

Re: How far should I go with my '41 flathead
 

Both of my 41s ( very early 3 piece fender ) have slingers and no rope seal . I also thought that the rope seal started in 42 . Memory gets slim in the later part of the day . Maybe its the coffee that wakes up mu memory?
As far as the work you want to do , some questions . How old are you ? Are you capable of doing the work yourself ? Are there known good flathead mechanics and machine shops around you ?
Are you aware of the difference between a slinger and a rope seal ? Check out what a slinger is if you didn’t.
Good luck, Gary

Re: How far should I go with my '41 flathead
 

There’s got to be a reason it runs hot.....how hot? .....if it boils over every time you drive it, that’s going to ruin it anyway......if it was mine, I would figure that out first and go from there.....if you have to take it apart to fix the overheating, then prepare yourself for at least a partial rebuild.......Mark

Re: How far should I go with my '41 flathead
 

With the engine out it is a good time to remove the welsh plugs (which can rust through) in the oil pan rails and scrape out as much foundry sand as possible from the rear of the block and the front. Can run clean water in the block with the plugs out and the block on an engine stand. You can get replacement plugs from your local John Deere parts dealer.

Re: How far should I go with my '41 flathead
 

I think this is good advice. A new seal will leak some. They all do. You could be opening a can of expense and aggravation for little improvement.

Re: How far should I go with my '41 flathead
 

I’m pretty sure the 41 was the first to eliminate the welch plugs on the bottom.

Re: How far should I go with my '41 flathead
 

I have the money to do it right. I'm more afraid of being wasteful or touching something that would be better left alone. Thanks for the advice!

Re: How far should I go with my '41 flathead
 

It leaves quarter-sized spots up and down the drive when I've pulled in or out and I put a pan under it to catch the drips. I am pretty sure the seal is leaking (the head gaskets were just replaced). There are also leaks from the bypass filter canister too and it's tough to quantify how much coming from where.

Re: How far should I go with my '41 flathead
 

I'm 46 and just learning....I'm capable doing some work myself, but probably not this. There is no Flathead expert I'm aware of in my area (La Crosse, Wisconsin). I have no idea what a rope seal is...I'm going to Google that now! Thanks!

Sam

Re: How far should I go with my '41 flathead
 

Your engine may or may not have a rope seal . . . it may have only a "slinger". If you have to pull the engine, maybe it is a good time to go through it? Heck, it is Winter - you need a project! LOL.

I'm sure there are some good flathead shops in WI - I'd inquire about that and see what you can find out. Having it run hot is never good - that is what can cause block cracks. Getting it sorted out now (as you have to pull the motor) is a good thing in my book!

Re: How far should I go with my '41 flathead
 

I'd look for another block, Preferably, a 59 series and have it rebuilt. That way, you've upgraded the engine to a better design more power at the same cost/ You can also use an 8ba block but that gets complicated. AT present I'm building a 59 block into an 8ba. Learning things like this is referred to a "backyard engineering" but is quite easy.
Gramps

Re: How far should I go with my '41 flathead
 

In Oshkosh WI you have Flatjack9 here on the barn. He can handle your engine issues. Dave/Green Bay

Re: How far should I go with my '41 flathead
 

As for leaving quarter sized spots on the drive...well, you may have to get a bit used to some of that. :)