felpro head gasket farmall 140

hardpan99

Member
Hi,

I know there's a lot of head gasket posts but I still am unsure about my situation. I'm currently finishing an in-frame rebuild on the 140. Head professionally done etc. I put my felpro 7900s gasket on clean and dry because felpro says to put it on clean and dry. The 7900s has a silicone seal coating according to felpro. When I filled her up with coolant it seeped out between the block and head mainly on the manifold side, but also a few tablespoons in the oil after a few days. Note that I did not run it because it was so cold and still have not. I've just drained the oil and coolant for now.

My question is: With the current leaky head gasket should I fill it with fluids and immediately start the tractor and get it hot hoping it will seal? Or would you recommend putting a new gasket on with copper spray sealant first?

Thank you!
 
I would stay with what Fel Pro said but start it and get it to operating temperature for a half hour, then retorque it. All the head bolts should move. How did you lubricate the head bolts when you installed them? Did you lubricate under the head of the headbolts. We have also found that some gasket will leak in cold weather but will not leak when warm. It is the material in the gaskets. More questions, post an e-mail.
 
I cleaned out the threaded holes in the block the best I could with compressed air. I lubricated the bolt threads and under the bolt heads/washers in accordance with the service manual. I did reuse the original bolts and now I wonder if I should have got new bolts. I didn't notice any obvious stretch to the bolts but I did notice when I first torqued them that the bolts would keep turning while holding at 85lbs for example. Not sure if that's typical.
 

I should add that when first torqued, the bolts would continue to turn slightly at any of the 3 successive torque values I aimed for. It was the first time I've done that so wasn't sure what to expect.
 
The issue may well be the turning at torque you describe. The staged torquing should be done, but the torque is not to spec
till the wrench does not move at that setting. The sequence before the final stage is OK to not quite stop. Uniformity is
more important than precision. On those tractors and cars from that era, the bolts were reused unless stripped. If it was
cold where you were working, the gasket may have compressed slowly. If the sleeves you installed were a little tall on the
rim, and/or the block had been planed a tiny bit to flatten it, the gasket can also leak. The sleeves can stick up not to
exceed about .004" if I recall. I also recommend retorquing after getting it warmed up. Each bolt or stud nut should be
loosened a tiny bit of rotation (2 degrees kind of tiny) then tightened to torque (until the wrench stops turning at that
torque (this is done to one at a time, do not loosen all then tighten). I like a click type wrench that ai can slowly pull
to the click. This limits the doubt about when torque is met. Jim
 

If you apply pressure to 85 ft.lb in your final sequence you may have to go around a couple times until it no longer turns when you reach 85 ft.lb no matter what torque wrench you use. However usually its only a couple bolts that will still turn just a little when you reach your final torque value. If you have that issue with all the bolts get another torque wrench.
If your head was milled and you checked that both the head and the block were ok straight and level length, width and cross ways sleeve protrusion is as noted previously you shouldn't have a problem. As far as torqueing the Idea is to bring the bolts up to the specified torque in 2 or three equal sequences following the required pattern shown in your manual and stopping as soon as you reach the torque value of 85 foot pounds. Make CERTAIN you read it correctly and your using the Foot pounds ft.lbs value and Not Newton-meters or inch pounds, either of the last two Nm or in.lb would not be enough torque for the head if set at 85. if your using a dial torque wrench or a Beam Style Torque Wrench with a pointer you simply stop when the needle or pointer reaches the torque value required in foot pounds by the manual. Note; That the beam style is typically not very accurate. The click type torque wrench's simply do just that they give just a little and click when you reach the torque setting most folks like these better.
Best of luck with your project
Byron
 
Update: I took the head off and checked the block flatness and sleeve protrusion. Block seems fine. Sleeves 1,2, and 4 all had equal protrusion of .003-.004. Spec is .003-.007. Sleeve 3 was visibly sticking up more than the others and is about .015 on one side and .018 on the other! This is definitely part of my problem. I'll pull the sleeve and take to a shop to get .012 removed if I can't find a reason why its sitting high.
 

Thanks to those who took the time to help me out. I think I've got it figured out. I went through 3 head gaskets and I made some rookie mistakes but learned a lot. I think my attitude when first approaching this was "hey, what could go wrong using new parts? Just slap it together!"

Some key things I learned:

1. make sure sleeve protrusion and flatness is in-spec
2. take the manifold off even if it makes a good handle
3. make sure the head bolts are clean and lightly oiled
4. make sure the bolt holes are clean
5. be absolutely consistent as possible when applying torque
6. let the gasket sealant dry to tacky before putting the head back on
 

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