Leaking Head Gasket

A few weeks ago I noticed a little wetness on the fuel pump but couldn't really tell where it was coming from. No puddles so I figured maybe a valve cover gasket leak and put that job on my to do list for spring. Then I started noticing small coolant puddles under the recovery bottle area. Tracked that leak to the vent port near the top of the bottle, Weird I thought. Started doing some reading on SS and it revealed the possible Head gasket. I drive my 1028 as a daily driver and put about 50 miles a day to and from work. Last night I borrowed a coolant pressure tester from our mechanic at work. When I got home late, I opened the hood and squeezed the upper hose; It felt inflated. I have never done a head gasket before and am questioning my competence on this job. Can someone give me a ball park figure a shop will charge for this job, or are there too many variables involved. Any thoughts and input on doing the job myself would be greatly appreciated.

Might be a leaky water pump if you have gotten water on your fuel pump... the leak under the coolant recovery bottle is most likely a bad radiator. but with out pics just saying....

$800-$1000 a head to R&R.

With this being your daily driver, and you in WI in winter(unless you have a warm garage), it might not be a good time for you to do this job yourself. Otherwise, it is not a difficult job to replace head gaskets. You will need decent tools, including torque wrench, a good place to work for at least a day, maybe more. Try to be neat and organized while taking apart, take your time, carefully follow some good instructions from good manual or TM.

If you think engine may have been over heated at any point, it would be good to have heads checked for warpage also.

Westech said:

$800-$1000 a head to R&R.

Click to expand...

Am I understanding that is per head? Is this a do in pairs kind of job?

I am just putting mine together after doing the head gaskets. Most of the time is spend scrapping and cleaning the block surface and prepping for the new gaskets. Have the heads cleaned, checked for flatness, and checked for cracks at a machine shop. Mine were flat and only had one typical crack between the valves, I bought the sleeve repair kit on ebay and sleeved all the coolant passages between the valves on both heads to prevent leaks in the future.

The kit is not made any more, so you may have to find a shop that knows about this repair kit and hopefully has one. As far as time, if you have everything ready to go including heads, you could knock it out in a day. It took me 2 weeks because of waiting for parts and only working on it after work for an hour or two.

After much deliberation and soul searching I have decided to not tackle my head gasket repair but instead sell my first and only M1028 and M101a2 trlr. It will be listed on SS classifieds tomorrow after I upgrade my membership. I wish I could keep them but it is time to move on and give them a good home with someone who has the funds and experience to keep them going. Thank you for the education and fun of owning one of these cool vehicles and all the thumbs up I get driving it 50miles a day. God bless you all and Merry Christmas. Keep an eye on the classifieds for photos and contact info.

If you just want to sell your truck that's fine I understand. However I think your jumping to conclusions that it's a head gasket. For starters does the truck start hard, or run poorly? Are you getting steam out of the tail pipe? Have you pulled the glow plugs on that head to inspect them? have you done a compression test? Did you actually do the leak down test you talked about?(with the engine cold). All these things need to be tested before anyone pulls apart any engine.......Ah month ago mine had an intermittent coolant leak (Under the radiator). Sometimes it would hold pressure, sometimes not. I almost ordered a new $300.00 radiator. Turned out to be a small leak at the upper radiator hose fitting. $20.00 & 5 minute fix.

Did a pressure test on the coolant system yesterday with a friend and charged the system to 15psi. It held for a short time and then I started the truck. At idle psi slowly climbed to about 22 in a matter of 3-4 minutes. I am no mechanic, but everything I read points to compression leaking into coolant passage. If there is another prognosi someone is willing to explore, my loss is your gain. I don't have the time or resources to tackle this project and the wife doesn't want another yard ornament (even if I decorate it for Christmas). It is time for me to move on. Look for the two vehicles to be on classifieds later today.

Well if you have a pressure tester in place of the radiator cap , of course the pressure would build when you start and warm the truck. Your radiator cap is a pressure relief valve that opens at 16 PSI. The pressure tester doesn't... This is why you pressure test the system cold and with the truck off so you get an honest reading. And sometimes leaks only happen when things are cold. Thus the reason you find coolant on the ground in the morning , but can't find the leak when the truck is warm.

Drock is right on. You may be jumping the gun in assuming its a head gasket gone bad. You said it held pressure for a short time. Were you unable to find any leaks while it was cold and under pressure? How long did it take for the pressure to bleed down? I did a pressure test on mine when I first got it and I could hear the leak. Ended up being two loose radiator hose clamps. Take a deep breath, grab a friend and a flashlight and try to locate the leak.

Question is how much you want for it ? Or.. I am willing to fix it for a small fee.

I have done many many headgasket jobs on GM 6.xx engines.
I don't think I have ever seen a Headgasket leak externally on a 6.2. You get either compression in the coolant or start burning antifreeze. You could have a cracked head or block but that is generally a 6.5 issue. 6.2's used crappy headgaskets called Printoseal from Fel pro. They are garbage and at some point most 6.2 will need them replaced. If you can change headgaskets on na small block chevy, you can do a 6.2. It is by far the Easiest diesel to work on.
Use 6.5TD headgaskets. They have better fire rings and set the stage for a future turbo . I would also strongly recommend
ARP head studs. The old headbolts are not reusable and I personally don't care for Torque to yield headbolts, especially doing the job in truck. Of course Headstuds require careful installation and sealing but will give you a much better job.

For starters, Start the truck ice cold and see if the upper radiator hose gets hard. That is a sure sign.
Once it is running and warm looking in the radiator(be careful removing a hot rad cap) and see if you see alot of big bubbles. Another sure sign.
If you have white smoke from the exhaust that smells sweet, you are burning it. GM cooling tabs might buy you some time with that scenario.

The truck starts easily as usual and sounds fine running. Does not seem to be burning coolant as I don't see white smoke. Upper radiator hose, which was replaced last year when all hoses were replaced with the radiator, gets hard like it is inflated. No visible leaks other than wetness from the breather port next to the cap on the overflow bottle. Have not started the truck with the rad cap off to look for bubbles yet; could do that tomorrow morning. I would love to keep the truck and work on it at my convenience when the weather gets warmer, but I don't have the garage and time to do this truck justice. I don't have a mechanic that I trust to do the job and not find other issues internally to help pay off his Christmas debt. It's been a pleasure owning this truck and I put a lot of money and love into it, but I have to know when to part with it to someone with the resources and knowledge to give it a good home. The body is solid with minimal dents, and no serious rust. That alone is making it hard to part with.

Too bad your not closer. Perhaps take Westech up. Rock hard upper is generally a sign. Hgs are no big deal . I can do them in about 4-6 hrs depending on how it comes apart and how much beer is in the fridge.