Head gasket repair

[Brando_SLT]

More slow progress. Between two jobs, bad weather, holidays, and sinus infections I have gotten the new heads installed. Since it's raining again, I'll go back to cleaning. If I catch a break in the rain I will get some rockers and pushrods installed.


Cylinders looked good, no scoring or cracks in the bores that I could find. So I hope that's a good sign. The driver's side head gasket was separated and I could see some blow-by around the rear. I cleaned up the mating surface with some brake cleaner and a billow pad - gently - before wiping it all down and wiping the inner cylinder bores with a lightly oiled towel. I did try to clean some of the carbon buildup off the cylinder tops, in hind sight I may have lost some added compression lol. Also brand new fuel injectors, completely new gaskets for everything. Should be really nice and leak-free on reassembly.

 

[OCDTech]

People will think i'm nuts, but been told this all my life, it actually happened to my dad. When i was like 5 or so he had an old truck with lots of miles, He did what he thought was right which was have the head done, seats tight, shaved etc. Soon after he put it back together, the rings "washed out" started smoking. Theory is put a tight new head on ann old motor and the lower end cant take it. If i was to ever do the same thing, and did to my Subaru outback ( 185,000 miles ) i wouldn't have the head done. You do need to take a good straight edge and make sure their not warped! Been 10,000 miles , doesn't burn a drop of oil.

Engine parts wear together.

 

[LoneWolf3574]

More slow progress. Between two jobs, bad weather, holidays, and sinus infections I have gotten the new heads installed. Since it's raining again, I'll go back to cleaning. If I catch a break in the rain I will get some rockers and pushrods installed.

View attachment 194672
Cylinders looked good, no scoring or cracks in the bores that I could find. So I hope that's a good sign. The driver's side head gasket was separated and I could see some blow-by around the rear. I cleaned up the mating surface with some brake cleaner and a billow pad - gently - before wiping it all down and wiping the inner cylinder bores with a lightly oiled towel. I did try to clean some of the carbon buildup off the cylinder tops, in hind sight I may have lost some added compression lol. Also brand new fuel injectors, completely new gaskets for everything. Should be really nice and leak-free on reassembly.

View attachment 194673
View attachment 194674

Are those pictures what the piston tops looked like after you pulled the heads?

 

[Brando_SLT]

Are those pictures what the piston tops looked like after you pulled the heads?

Yep. Something to be concerned about? I mean, besides it being a high mileage engine...

 

[Brando_SLT]

More progress... Pushrods and rockers installed, valve covers too. Re-ran the wiring harnesses and started plugging things in. Cleaning took up most of the time for the intake, plug wire harness, new fuel injectors, and lots of other plastic bits. New seals on everything as well. I am going to clean off the top of the engine before I put the rubber pad and intake back on. Also taking the time to treat any and all rust I can find.

 

[LoneWolf3574]

Yep. Something to be concerned about? I mean, besides it being a high mileage engine...

Nope, I was just curious. All things considered, they're pretty clean IMO.

 

[Brando_SLT]

More progress today. It's starting to actually look like an engine again! Intake manifold installed, alternator, a/c compressor, coils, coil and injector harnesses, 180° thermostat, coolant outlet housing... Pretty productive.

I did learn that the ARP exhaust bolts and studs that Summit Racing sells will NOT work with stock exhaust manifolds. So I had to order OEM replacements. Also a new MAP sensor is on the way, and replacement heat shields. I was almost tempted to buy new coils too because they were looking a bit corroded on the inside connector. All in all, today was a good day!

Side note, where can I buy replacementss for the black plastic clips and retainers? A bunch of mine broke due to age/heat. Thanks!

 

[jerryt]

You are a brave soul to try a project like this outside and with time constraints. Maybe if I was 36 instead of 76 I would try it too. I wish you the best of luck. It seems like you are doing a good job. Keep us posted on the progress and outcome.

 

[LoneWolf3574]

Side note, where can I buy replacements for the black plastic clips and retainers? A bunch of mine broke due to age/heat. Thanks!

View attachment 196085 View attachment 196086 View attachment 196087

Clips and Fasteners might carry them, I really haven't looked for my truck, to be honest.

https://www.clipsandfasteners.com/

 

[Brando_SLT]

Another update... It's all buttoned back together, my last bit of parts showed up today - Map sensor and exhaust heat shields.

I bled the coolant system and reinstalled the drive belt. For ***** and giggles I cranked it over and it caught! I shut it down immediately, valvetrain sounded pretty loud so I'm thinking I should pull the fuel pump relay tomorrow and crank it until it's got good oil pressure. I checked the workshop manual and it only has a priming procedure for the 3.7/4.7 after installing a new oil pump.



And here it is holding vacuum with the vacuum bleeder. I'll have to do this a few times to get all the air bubbles out.

 

[Brando_SLT]

Whew... What a day. I lit her up today. As expected, still quite a bit of white smoke to burn out of the exhaust. I plugged in my OBD reader and ran Torque - still getting a CEL for "P0118 - Engine Coolant Temperature Circuit High Input". I recall when reconnecting the coolant temp sensor the plastic end on the sensor spun around easily - electrical connection might be broken? I'll look into it more tomorrow.

It's idling a bit high, around 800-820 and smells like it's running rich - so the ECU might think it's still in "warm-up" mode, even though the temp gauge reads about 5º left of center. I also made a video:


Thoughts? Comments? Ideas?

 

[LoneWolf3574]

Just an FYI about the oil pressure gauge, FCI engineers made it a dummy dial. Meaning that when the pressure drops to 4psi, then the needle moves to the low pressure and you get the check gauges light and bell. I about soiled my pants when my sending unit failed in the middle of a left turn at an intersection and my gauge dropped to 0psi, one of those pillar pod gauges is on my birthday wish list because of that.

 

[Brando_SLT]

Good news everyone! I think I can put a fork in this job and call it done. Replaced the faulty coolant temp sensor this evening, reads 185° under heavy load from my scan tool.

CEL is now gone but it still needs to go through a few drive cycles to do the EVAP and emissions readiness. Hopefully my EVAP leaks gone now, too. Just in time to get it smogged

Thanks for following me along on my adventure.