She got hot and runs rough now.

[914turboford]

I put a used 6.2 in my '85 K10. The stupid block heater retainer was broken so I rigged up something that lasted for about a month. Then my wife was driving it and it lost about 3 gallons of coolant before she looked at the gage. Towed it home and put some water in it the next day and started it up. It idles but it runs rough. I am thinking I should fix the freeze plug and at least try driving it a little to see if it overheats. If by some miracle a head is not cracked or a HG blown, what else could cause the rough running? It was not blowing any steam when it was idling rough. Also, if there is serious engine damage would it be likely that the short block escaped relatively unscathed? I do have a good set of heads I can throw on. I don't relish another engine change.

[twaddle]

If you checked the cooling system for bubbles at the radiator cap area I would suggest you fill the expansion tank right to the top with water then run it to check for steady or constant bubbles into the expansion tank.
Checking it at the radiator is difficult so do it at the expansion tank.

You can still have a blown head gasket and not lose any coolant or get gas into the radiator as it could be blown between two cylinders (this would cause rough running). A cylinder compression test would be required before pulling heads off.

Be careful about continuing to use the engine as if it have had a good "roasting" the pistons could have picked up on the cylinders.

Sorry but it doesn't sound too good.

Good luck

Jim

[914turboford]

It seems to me that if it runs warm I should just pull the heads. I don't have a diesel compression tester.

[twaddle]

You can pull the heads off if you want but there is nothing worse than ripping something apart and ending up staring at a load of healthy parts that have to be put back together.
I always prefer to spend some time testing so that some evidence can help you head into the area where there is a fault.
A compression test would (hopefully) point you in a direction as to which cylinders may be down and in the long run save time and money.

Is there anywhere you can beg, buy or borrow a Compression tester. If you can get one with an adaptor to connect into the glow plug holes that would also save some time as you don't have to remove injectors and fuel pipes.
I would take out all glow plugs before cranking the engine over for the Comp test as this puts less strain on the starter motor and batteries.

Are you getting any white smoke at the exhaust when revving the engine?

Good luck.

Jim

[NH2112]

Every 6.2l/6.5l owner should have a compression tester, IMO. For about $50 you can have one.

http://www.amazon.com/Diesel-Compression-Tester-Only/dp/B000HI7DUU/ref=sr_1_7/002-4118515-3264046?ie=UTF8&s=automotive&qid=1188125077&sr=1-7

http://www.amazon.com/Diesel-Engine-Compression-Test-Adapter/dp/B000HI36HY/ref=sr_1_38/002-4118515-3264046?ie=UTF8&s=automotive&qid=1188125162&sr=1-38

[warwagon]

how's about pulling the dipstick. if ya did, what color is that oil? how's that oil smell? just a lil' something to look @. that would have been my 1st look, then to see if you have oil in the rad., good luck!!