flat head Rebuild or not to rebuild
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flat head Rebuild or not to rebuild
First off I like to thank everyone with all the great info on helping with the build of my 51.
I did have a problem with the front crank pully, it had a little knock,pulled it off and the pulley was worrard out. The woodruf key damaged i need to replace. i did find another pulley the the stamp reads 8ba 6312-c12 maybe g-12 not sure.I know its not what the manual reads. It does line up fine .
The difference it is for a thin belt.Being equal will it work?
The motor was running pretty good before I tore it down, but after sitting 20 plus years I wanted to check out the condition.
Ridge on the cylinders .014-016 have not mic yet. Alot of carbon build up on the valves.Still have to tear down to mic main, rods, cylinders.
My biggest concern at this point was the amount of rust in the block.i did a compression check it was around 45 all cyl. I know it was low but maybe the rings are stuck.There was not water in oil. I was thinking to tear down
check block to be sure all is well . Bake and blast and new cam bearings
At this point of no return rebuild or put back together and drive.Alot of ifs.
BTW this is a recon motor. no history thanks George
I did have a problem with the front crank pully, it had a little knock,pulled it off and the pulley was worrard out. The woodruf key damaged i need to replace. i did find another pulley the the stamp reads 8ba 6312-c12 maybe g-12 not sure.I know its not what the manual reads. It does line up fine .
The difference it is for a thin belt.Being equal will it work?
The motor was running pretty good before I tore it down, but after sitting 20 plus years I wanted to check out the condition.
Ridge on the cylinders .014-016 have not mic yet. Alot of carbon build up on the valves.Still have to tear down to mic main, rods, cylinders.
My biggest concern at this point was the amount of rust in the block.i did a compression check it was around 45 all cyl. I know it was low but maybe the rings are stuck.There was not water in oil. I was thinking to tear down
check block to be sure all is well . Bake and blast and new cam bearings
At this point of no return rebuild or put back together and drive.Alot of ifs.
BTW this is a recon motor. no history thanks George
Post Fiend
Joined: May 2008
Posts: 7,641
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From: Poway, Ca.
Well if an engine has been sitting that long it's will show lower compression because everything is not lubricated well and probably a little stiff.
I think the more narrow pulley you are talking about is off a car engine.
I was taught that once you pull an old engine apart to this point, it's not good to put it back together. Engines parts tend to wear in together and that's been disturbed now.
So, I'd rebuild it - No gambling that way.
I think the more narrow pulley you are talking about is off a car engine.
I was taught that once you pull an old engine apart to this point, it's not good to put it back together. Engines parts tend to wear in together and that's been disturbed now.
So, I'd rebuild it - No gambling that way.
Fleet Owner
Joined: Jul 2004
Posts: 27,283
Likes: 1,046
From: NM
If the ridge is really .014 - .016, there can't be much left of the rings, and a gap as wide as the Mississippi. Crap on valves will also kill compression. I took mine apart and put it back together, but I kept track of where everything went (valves, lifters, pistons/rods, etc). It does fine. But I think your engine must have a lot of miles on it, a good clean-up may not do a lot of good. Check it out thoroughly before you make the commitment, don't want to find cracks after you've poured hundreds into it. Is it .014" over standard bore? You've got plenty of meat to work with if so.
The narrow belt crank pulley is for a car system; you can use it if you change the pulleys on the water pumps, fan, and generator. But 8RT wide pulleys are easy to get, that's undoubtedly the easier path.
The narrow belt crank pulley is for a car system; you can use it if you change the pulleys on the water pumps, fan, and generator. But 8RT wide pulleys are easy to get, that's undoubtedly the easier path.
Senior User
Joined: Oct 2010
Posts: 171
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From: Long Beach/Crestline, Ca
The nice part of digging deep into your wallet at this point is a full on rebuild, bore cylinders,new pistons,crank turned,new oilpump,new cam gearset,valves ground. Is knowing you'd trust the engine to drive across the country with no trouble. The price is forgotten long before the quality wears out. I have a hard time remembering exactly what my 239Y cost me, $ 875.00 or abouts. Never regretted the money spent. 18 odd yrs later and it still runs like new.
Fleet Owner
Joined: Jul 2004
Posts: 27,283
Likes: 1,046
From: NM
I'm afraid the days of $875 rebuilds are long gone; a dollar then is about $3 or more now. I'd figure a minimum of $2k assuming it has to be bored, new pistons, full valve grind, polish the crank, new bearings, but the cam and lifters are OK. A gasket set is about $150 nowadays. You could easily double that number if you don't exercise restraint. But I agree, if you know the truck is a keeper, having a bulletproof engine is a great start.
Like I said, I took mine apart to see what I had about 5 yrs ago. I found date stamps on the bearing shells from '74 and '75 (Clevite production dates), a very clean crankcase, and other indications it was rebuilt in the '70's. It has some taper on the cylinders and a couple of valves are a little loose, they tick. But I've run it all over town for five years very reliably for the cost of my time and a set of head and oil pan gaskets. Now that the truck itself is squared away, I'm going to take the plunge and put everything right so I can hit the open road.
Like I said, I took mine apart to see what I had about 5 yrs ago. I found date stamps on the bearing shells from '74 and '75 (Clevite production dates), a very clean crankcase, and other indications it was rebuilt in the '70's. It has some taper on the cylinders and a couple of valves are a little loose, they tick. But I've run it all over town for five years very reliably for the cost of my time and a set of head and oil pan gaskets. Now that the truck itself is squared away, I'm going to take the plunge and put everything right so I can hit the open road.
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Senior User
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From: Long Beach/Crestline, Ca
I'd looked a long time to find a 55 unmolested enough to suit me. So i knew it was my keeper. Low mile =65k, Low owners i'm 3rd, Local so calif truck i even ran down the orig owner in the next town over from an old registration in the glovebox. Man was he tickled to see the old truck. Even dug out a picture of it when new with the 35 Ft 1955 travel trailer they order it up to pull. Thats why it had the 5.88 gears and all the fender n tail lights massive bent C channel bumper/tow rig. But back to the point. Unless it's a quicky turnover for a fast buck, don't skimp on the drivetrain.
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Senior User
Joined: Nov 2008
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From: Hillsboro, Or
I rebuilt mine from the bottom to the top. Yes you can get a little carried away when doing the rebuild. Also shop around for your parts just don't go with the first person that sells the part.
Senior User
Joined: Oct 2010
Posts: 171
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From: Long Beach/Crestline, Ca
Good point. As i remember mine took about 2 weeks because the shop doing the work didn't like the prices they we're finding on the 239Y and didn't want to pass the high cost on to me. Saved me about $200 by digging around for the best price on the pistons,gaskets and such. And as i was in no real hurry it all worked out.
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Thanks every one for some good advise. I know we are looking around 2k and that is not including any mods like heads sling shot intake or nice dizzy. oh yes that name that TUNE CAM.Think Iam going to the machine shop and talk to the old boy and get a game plan,Then pass the hat!! LOL
I did take the feel test on the ridge in the cylinders with my feeler gage in the other hand ( not to percise but I think it is more like .003 , may be wish full thinking.) I see some of these motors in access of 6-8k or more
That is alittle more jingle than I want to go or have.We used to have a A model at the ranch and I swear it was held to gether with bailing wire and what ever we had to make it work. Sure wish I had the Roadster pickup now.
I did take the feel test on the ridge in the cylinders with my feeler gage in the other hand ( not to percise but I think it is more like .003 , may be wish full thinking.) I see some of these motors in access of 6-8k or more
That is alittle more jingle than I want to go or have.We used to have a A model at the ranch and I swear it was held to gether with bailing wire and what ever we had to make it work. Sure wish I had the Roadster pickup now.
Senior User
Joined: Oct 2010
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From: Long Beach/Crestline, Ca
Trick heads,better flow intake,dizzy, all work best on a solid foundation, Owning a 1914 Model T i know/heard all the storys of filing the rod caps,cutting up your leather belt to pad the #1 rod bearing to get a few more miles out of the old truck. But keep in mind the T and A are both very low speed engines. 1600 max RPM for a T. Max tq at 900. You can idle a T along in high gear at 200 rpm. At the least i'd have the crank turned and a new oil pump. I've done and seen to many shortcut builds that started knocking 3 to 5k later.
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