need some advice

[felix37]

I got this flathead from a friend, who had it rebuilt by a machine shop that has experience in rebuilding flat heads. He had the engine built for one of his cars,but he sold it and the engine sat in his garage. This past summer his shop was flooded and water got into the motor. once I got the motor home I took off the heads and intake to inspect the motor,there was a little rust residue in the cylinders as well as the valves,I sprayed it down with WD40 and cleaned things best I could.
My question for you all is.. what is the best way to clean this motor up or what would you all do?? also when I removed the heads I noticed the center bolt holes had heli coils in them (two on each side of the block) with hairline crack below. Is this the proper way to fix this? should I be worried?? your advice is appreciated!

[Binx]

You're bolt hole repairs are typical --if not overdone. Most blocks that have service life have those cracks. As long as there is only one crack extending from the bolt hole to the water jacket, you're good to go. Another crack leading to the valve pocket -- not so good. As far as the flooding, My opinion is if the motor had been test ran, then you're probably okay because oil is pretty impermeable, but if you found fluffy looking rust in the cylinders, you'll need to pull the pistons. Cylinders get the least lubrication and are most susceptible to corrosion. Cylinder wall corrosion and stuck rings may be your biggest issue. If you have the means to run the engine, a lot of guys will say change the oil, soak everything down with Marvel Mystery Oil and fire that mutha up!! I'm good with that too.

Lonnie

[Kahuna]

Binx
Lonnie gave you good advice

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Originally Posted by Binx

You're bolt hole repairs are typical --if not overdone. Most blocks that have service life have those cracks. As long as there is only one crack extending from the bolt hole to the water jacket, you're good to go. Another crack leading to the valve pocket -- not so good. As far as the flooding, My opinion is if the motor had been test ran, then you're probably okay because oil is pretty impermeable, but if you found fluffy looking rust in the cylinders, you'll need to pull the pistons. Cylinders get the least lubrication and are most susceptible to corrosion. Cylinder wall corrosion and stuck rings may be your biggest issue. If you have the means to run the engine, a lot of guys will say change the oil, soak everything down with Marvel Mystery Oil and fire that mutha up!! I'm good with that too.

Lonnie

Great advice Lonnie. The only thing I'd add is if you're going to pull those pistons run a hone down the cylinders to clean them up. It all depends on how much rust and how far it got into the metal.

[felix37]

thanks for the advice! another question. can the cylinders be honed lightly while pistons are still in. I was wondering if I could rotate the piston to the very bottom and do one at time very carefully???

[Brendan]

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i had a Falcon that had got flooded, i drained 5 gal of water out of the motor, them i put in dome diesel and oil to flush it out. and changed the oil a few times. it ran good but it would burn a qt of oil about 20 miles. i think the best thing is to take the motor apart and clean all the parts. you could have got silt in the barrings and on the cam. the only way to get it off is to pull it apart and clean it... Brendan

[western77]

Your rust issue does'nt sound any more severe than a motor that sits all winter in a Michigan garage and experinces condensation. Make sure there's no water in the crankcase and follow Lonnies advice. JB

[Randy]

I wouldn't hone it with the pistons in, because there's no way to get the grit out, the metal removed with the hone, and it'll probably wipe out your rings when you fire it up.

[Mike51Merc]

Nice engine! Just to echo the points above, the cracks you have are common and generally not a problem. Most people don't heli-coil or do anything about them.

Regarding the water, if the flood water was clean I wouldn't do anything more than inspect the cylinders, replace the oil, and fire it up. A little water on the insides will evaporate pretty quickly. If it was nasty mucky river water, then I'd want to disassemble and clean the insides real good.

[Gumpy]

if the motor was completely flooded i would take it apart its already on the stand...the water movement may have dislogded rust particle in the water jackets,,,I would pull the main caps and pistons just for piece of mind...just my 2 cents---gump

[Ol' Ron]

I go with Brendan. Looks like a nice engine, why take a chance. Firing it up might work. Might not. stupid is, what stupid doz

[felix37]

When I dis assemble the motor should I remove the valves as well? also will I damage the rings when removing the pistons?? any other precautions,tips,advice? This should be good practice for me as I want to rebuild the 39' 81-t motor (by myself)that is in my car now. I have several how to rebuild Flat Head books laying around, but none of them cover the dis assembly of a freshly built engine that has never been started but got caught in a flood. Thanks in advance

[Mike in AZ]

take lots of pics before you take stuff apart....disassembly will be the same as old engine, 'cept hopefully stuff isn't seized....and you won't be fighting all the grunge and grease, etc.....good luck....Mike

[felix37]

Thanks! I'm going to give it a shot!

[peewee2you]

Felix, while all the above is good advice, I think it depends on your automotive knowledge and experience, as much as you can take an engine apart you can't just put it back together, another words, there are torqueing of bolt issues, clearance issues, ring direction issues and so on. If you are technically and mechanically inclined and have the appropiate documentation and books for the required spec's when putting it back together by all means proceed. However, these motors are quite costly these days to rebuild should you put it back together wrong and experience a problem like the one you are trying to stear away from now. My intentions aren't to scare you off, but perhaps the minimal charge of a machine shop to tear it down clean it up and put back together might be a better way to go, labor and gaskets might be all it needs at a shop. I know that the only way you learn is to just do it and I have learned a lot thru trial and error, but all schooling can and is expensive. Is schooling a word not sure

[TRUCK_RAT]

i few years ago i forgot to take the plug out of my boat over the winter. it sat all those months outside at a storage yard. when i got there the tires were flat. after draining the water that had filled the entire boat up for several months the tires stood up perfectly. anyways the motor was stuck but it broke free and about 5 oil changes later the oil was water free. ive been using the same boat with no other mods for several years now. but now i remember to take the plug out. ha

as long as the cylinders arent pitted i wouldnt worry about it.

[jimTN]

Ifc the motor is not stuck and will turn over by hand, you could force feed oil from the rear of the block (gauge sender port) till you pass about a qt or half qt thru the system. This would flush out the oil gallerys and makes things ready to turn over. Drain the pan after that and you should be ready. With those heads, it sure pays to use a sealer like copper coat on both the block and heads when installing.

[OLD...BILL]

Felix: YES take it apart, ( part way ) depends how wet did it get. Take the pan off and show us some pictures, I would pull the pistons and the crank, and stop there If ..if ..if .. again how wet did it get. ?? with the rods/pistons out, blow some air through the oil system from the oil output at the bellhousen back into the engine, and see what you get at the rod bearings oil ports on the crank,,, is it all oil ,,,,or water and oil ??? or all air. ??? this should tell you how much feather apart do you need to go?? If you get the oil system completlly clean, you need not take the valves/cam out, GO ahead and hone and clean the cylanders,,, maintain all bearing in the right oriantation, and the timing gear marks right again. Now its all back togeather,I would use a long neck funnel adaped to the oil pressure out port on the back of the engine, fill the funnel and let it run in and through the complete oil system with fresh clean oil ....and your good to go .... OLD....BILL

[Brendan]

Originally Posted by TRUCK_RAT

i few years ago i forgot to take the plug out of my boat over the winter. it sat all those months outside at a storage yard. when i got there the tires were flat. after draining the water that had filled the entire boat up for several months the tires stood up perfectly. anyways the motor was stuck but it broke free and about 5 oil changes later the oil was water free. ive been using the same boat with no other mods for several years now. but now i remember to take the plug out. ha

as long as the cylinders arent pitted i wouldnt worry about it.

rain water is clean, flood water is full of silt, imagine dumping sand in your motor ... not good

[Binx]

Felix37, heed the good advice here. Now knowing that the engine had never been run and was dry with probably only assembly lube before the flood, I'd pull the whole thing apart -- especially because of what Brendan said about the silt. With a dry motor, it is probably coated with silt on all the internal parts. Imagine emulsified clay in water. Seems slick running it between your fingers, but it is an abrasive on the micro level and will continually churn through the motor.

Glad to hear you want to use this motor as as practice for the '39 motor. I'm sure everyone here will be great help if you have questions. My tear-down advice is take lots of photos like Mike in AZ said. Re-read what Peewee2you said and if you decide to do it yourself, invest in lots of ziploc bags to bag-and-tag dirty, then more to bag-and-tag clean.

P.S. I have a half of mind to toss my motor in the river for a few days if it comes out looking like yours!

Lonnie