problems with H1

[ATCwizard]

I am looking to purchase a used H1 for a daily driver. However I have noticed that most early models have there engines replaced. Why is this, and what other problems could I expect with buying a used H1?

[waterboy333]

lots of h1's crack a cylinder due to overheating, there are aftermarket crossover kits to solve this. maintenance is key in a hummer, i recommend one that has seen the shop every year. look for a 98-99 for a better off roader at a good price. stay away from the earlier ones if possible. 99 gets tt4 and has abs. other common problems are pumps, abs modulators, and idler arms

[USMILRET]

It's not that they are cracking a cylinder because of overheating it's because of blowing a head gasket. The 6.2's and still the 6.5's are susceptable to overheating in the military. The 6.5's are better suited for military and non military use.
They will crack between the cylinders with Extremely excessive heat but excessive heat is the bane of these engines. The water crossover kits only permits water to get to the thermostat in a less restrictive state IMHO, Ok maybe a little water will crossover.

[Firehawk97]

Ok so I have been a Certified H1 technician since 2002. They dont crack due to a blown headgasket. The crack in the number 8 cylinder due to casting of the walls to be to thin. After time and milage goes by the begin to leak coolant into the cylinder. Thats a fact from a AM General field service rep. The years affected were 97-99, Customer complains low coolant light and no leaks. Remove glow plug install glow plug tester removed valve and apply shop while cylinder is at TDC, in about an hour or so the overflow will be blowing fluid out the tube. I have done about 10 engine for this concern. The biggest crack i have seen was 1 inch long and about the width of a pen point.

[corsair-pilot]

Hi.
Firehawk is 100% correct on this. As I was H1 tech from 1993 to 2006.
And change more engines than I can count.
Dale

[SirreDarre]

Att: corsair-pilot

Can you send me your email to [email protected]? I have a few questions for you as I'm in the planning phase of a Hummer project and I'd like to get in contact with a Hummer tech.

Thanks!
Simon

[jonathan2340]

I don't think there is any problem with H1. If you drive with carefully then this is best for you...