head question
 

When you blow the head gasket on a i4 or i6 I wanted to know some things that might be wrong with it when you do that?

How hard is it to change?
What some other things you can mess up valves, lifters, rings?
Will it be like a complete rebuild of the motor?


thanks in advance.

anyone?

Head gasket isn't particularly hard to change, but it is time consuming since just about everything bolts to the head and has to come off.

As for other things needing work... well, why did the head gasket blow? Did it overheat or did the gasket just fail from age? Usually when a head gasket goes, you can get away with just having the head checked for a good mating surface and magnafluxed to check for cracks then reinstall it (provided it's not cracked). However since it's a 91, I'd consider having the valve seals/guides done since the head will be off already and they are probably pretty worn. You may also consider putting in new lifters at this time. Lets face it, it's a 91 and probably has a lot of miles on it. While it might have run fine before the gasket failed, the parts in it are getting worn. You may want to consider just doing a rebuild since you'll be halfway apart already (or pick up a reman engine).

To be honest, though, it's hard to say what else will need to be done until you get the head off. If you pull the head and find a cracked piston or bent valves, well obviously that'll need replacing.

Unless you find something horribly wrong inside, it won't be a complete rebuild, although some people will call it a 'top end' rebuild, especially if you get the valve seals/guides done.

no its newer then a 91, I am looking at a new one to buy but it has a blown head gasket. I dont know much about it, someone just told me about it and I dont know much about heads so I just wanted to know like what I should look for when get it apart or will it be a simple replacement and good to go. It was owned by a mechanic so Ill be able to call him and ask him about it more.

Thanks for the info man, really appreciated.

Ah, well, in that case if it's a 99+ then beware. The heads on those tend to crack, which would require replacement.

Not to be negative but, do you know this mechanic? If not, he may just be trying to get rid of it because it's not worth rebuilding and he knows it. Hopefully this mechanic is a trustworthy type of person and will tell you everything that is wrong and why he/she isn't rebuilding and reusing or selling it for a better profit.
Good Luck

Cheap solution
 

Hi there. I just have to share with you some really good news. My 2001 2,5 TD XJ had a leaking cylinder-head gasket. I ordered some expensive (I won't mention the name) sealer from a wholesaler in UK (I'm in Norway) which never came. I had to use the car in the meantime and the leak got worse and worse. Finally the water just poured stright through the engine. When I say pouring, I mean it. Had to fill up water every three or four miles. I was also getting oil-mist on my back window. In desperation I went to my local accessory shop and bought all they had of a product called Wynn's Cylinder Block Seal. I had to use all nine bottles and still have the stuff in the motor.
Listen ....it works. My engine is again water-tight. No leak. Zero. Zilch. You might think that I work for Wynn's or have shares there. I do not and I don't care if you don't believe me. For those who do believe me - there is hope. Regardless, perhaps, of how bad your gasket is damaged. Wish you luck with your Jeep. I am again enjoying min.

More ...
 

I plan to drain the Wynn's from the system when I have driven about 500 miles, and replace with clean anti-freeze. I think that it is wise to disconnect the heater lines and use a u-section tube to complete the water circuit, whilst your gasket is being repaired. Also a good idea to remove the thermostat for the period of repair. A thorough flushing in both directions afterwards, before the anti-freeze.