Head Gasket Replacement-FJ55

southerncruiser62 · 07-31-09, 06:35 AM

Alright so some of you have probably been wondering why I haven't been doing keeping up on the board recently, well it's because for whatever reason I am bound and determined to make something of this here 55. I know I had mentioned that in the past I had been having cooling problems with the truck and thought after replacing the thermo and hoses that the water pump may have been clogged. Well it turns out that from the boiling coolant in the overflow container that the head gasket was gone, well actually the head gasket was fine it was a cracked head. So with the help of a few of our members I was able to located the sought after 1.5F head which in my case with the 79 block increases the compression slightly. Josh in High Point was able to help me out and I thank him for that. So then it was off to the machine shop for a magnaflux, new valve seats, seals, springs, and valve regrind with a small decking of the head. In the meantime I figured why not just start this project from the inside out, so new alternator, regulator, and water pump. Here's a few pictures to get started. Last photo is the common oil galley plug mod.

southerncruiser62 · 07-31-09, 06:39 AM

So next up was to reinstall everything, so starting with a 1979 head gasket as JimC said always match the head gasket with the head but in this case because the cylinder walls are larger than that of a 74 it required that I use the 79 gasket. Second Photo is where the oil galley hole to get oil to the rocker arm is, always need to make sure that isn't blocked when reinstalling the head gasket. Following that was a re-torque of the head and rocker arm installation. Be sure when installing the rocker arm to loosen the valve set screws so the valves seat properly then readjust for FSM specs.

southerncruiser62 · 07-31-09, 06:45 AM

So once the rocker arm was installed I moved on to the intake/exhaust. I was in debate on what to do here but since I had already put more into it than I anticipated I had decided to go back with the factory intake and exhaust, after getting it installed I found that the surface needed to be milled .003 and that was going to cause a problem. Not to mention the 6 potential areas for exhaust leaks through the combo. Well this led me to searching for 3FE manifolds which a IH8MUD member in OR was able to ship to me. I clearanced the mounting holes to match up with the 2F intake manifold and bolted here up. What made things interesting is that the seller didn't send the flanges to I had to have some made. Then off to Henry Muffler for a Y-pipe and installation.

southerncruiser62 · 07-31-09, 06:48 AM

Y-pipe and flanges, then off to the top side for carb installation, DESMOG, and air cleaner install. The Desmog went much smoother than I anticipated after trying to guage everything through the diagrams JimC and others had posted. I may reroute a few lines but all in all it was not to bad.

GarnerFJ40 · 07-31-09, 06:58 AM

That engine is looking nice....

77cruiser · 07-31-09, 07:09 AM

the cleanliness makes me jealous. I belive my trucks have not been desmogged. This helps a good bit with Gas mileage right?

southerncruiser62 · 07-31-09, 07:33 AM

I think more than anything it lets the engine breath better and increases performance, I don't think you will see a drastic improvement in MPG though

S4Cruiser · 07-31-09, 10:36 AM

That's alot of progress and a super clean engine.

Did you paint the valve cover or is that just the look after blasting?

southerncruiser62 · 07-31-09, 11:10 AM

It is painted with Heat temp. paint for up to 2000 degrees. as is the manifold and thermo housing. They were all sandblasted prior to painting.

Used the same paint for the head, manifolds and flanges.

Mtbcoach · 07-31-09, 01:14 PM

Damn Greg, you said it would look nice and you didn't lie. Very nice work, glad it all came together despite all the hurdles you had to jump through. Very well done...

rutbeer · 07-31-09, 03:53 PM

Awesome. Congrats on getting it back together. When I put my head back on, I found that one of the lifters had jumped slot on me.......lots of fun taking things back apart to get the lifter back in.
So....where's the turbo on this truck?

krzyabncanuck · 07-31-09, 05:49 PM

Darn Greg, engine almost purdy enough to eat off of now.

little_joe · 08-01-09, 05:12 AM

I totally dig the masking-tape block-off and the open air intake. Bet those mods get ya 11hp!

diggity · 08-01-09, 07:23 AM

Looking good Greg, let me know if you ever need a hand working on something. I am happy to help.

jfz80 · 08-01-09, 04:41 PM

looks great greg!

You guys are makin me jealous... gotta get a move on to have the piggy at our URE ride.
Whats the benefit of the 3F manifolds ?

Ive read so much im bout blue in the face but ive read of putting 3F heads on a later 2F but i didnt think a 79 qualified for that (thats what im building) again it looks great, youve got to love having that behind you and getting on or one step closer to the road.

southerncruiser62 · 08-01-09, 10:44 PM

well actually because the 79 has the domed pistons and a larger chamber head the early model F heads won't work. However because the late model 1973 and the 1974 had the 1.5F head and smaller domed pistons than the earlier models along with the enhanced oiling system for the rocker arms the 73-74 1.5F heads are ideal for the later blocks 75-80. Also with the large cylinder and domed pistons coupled with the smaller chamber on the 73-74 heads you increase your compression.

On to the manifolds, well for me it was the decison that besides the flanges and the head there were no other opportunities for exhaust leaks. With my original intake/exhaust combo I had the following potential leaks:

-Head
-Rams Horn and each end
-heat riser plate and bushings-both top and bottom gaskets
-Second 1 to 2 exhaust coupling
-Finally the downpipe flanges

To me the benefit of better flow and less potential leak areas warranted the enhancement. Granted I had to modify the exhaust slightly, but now I have a new stailess exhaust front to rear.

She has been back on the road for a quick trip around the neighborhood but now I am working on the rear spring to get it tempororarily fixed to make sure all else is fine and then come the suspension mods.

Mtbcoach · 08-02-09, 06:05 AM

Since that last post is so late, I'm hoping you weren't spending that whole time getting the shackles free. I didn't see anything on the news about a car fire so I'm assuming you were either successful or ran out of gas...

southerncruiser62 · 08-02-09, 06:51 AM

Succesful, I'll probably be coming by later to get the spring welded up if thats alright.

Mtbcoach · 08-02-09, 08:35 AM

No problem, glad you got it free...

1974FJ · 08-02-09, 09:20 AM

Holy Crap, thats sweet Greg! Good work!

jfz80 · 08-02-09, 10:17 AM

Yeah I had wanted to get an F.5 head for my build to bump up compression but the one i had is an early head and each one i found locally were also early F's; plus i had a perfectly good matching 2f head. Now you got me wondering about my manifold decision; so much for the budget rebuild

southerncruiser62 · 08-02-09, 10:52 AM

I don't want to start about budget, I never intended on taking this as far as I did but I thought. I am already here might as well not do it twice......then I am reminded about that top right gear.....

Fort Knox · 08-04-09, 11:53 PM

Awesome Greg! Agreed on your decision to do it right and not regret doing things differently. I assume there are no more cooling issues now, right?

concretejungle · 08-05-09, 09:18 AM

J, stop thinking about head and get that thing finished!!

southerncruiser62 · 08-07-09, 04:51 AM

well, first day back on the job and she did well.....and damn that 5th gear is cool. It's nice to be cruising 75 and only taching a little over 1,800 RPM's. It's tempting to put her on the highway sunday morning and head west.