Well folks no more than 1 week after I get my B18A powered 88 HF on the road the worst happens.....I've just found out about a major problem with my engine today. I was riding aound with a friend in my hybrid and I noticed I was smoking profusely. A couple of days earlier I noticed it too, seeing as how it was intermittant and given the amount of time the car had sat I figured on it being water in the gas or trapped in the muffler. However upon further inspection, with a fellow hybrider and my dad. We diagnosed the problem as a BAD HEAD GASKET! **** huh?

I did a compression test 1-4 (175,175,160,160) What is a good compression readout for an LS motor? I think new it's around 185 right? So I figure 175 isnt all that bad. I prolly just need a valve job to bump my compression back up. In hindsight, I think it did smoke way up top alittle

I figured that the head gasket is bad around the # 3 and 4 clyinders, causing water to seep in and my compression to be lower on thoss two than on #'s 1 and 2.

How hard is it to replace the head gasket? could it be accomplished in a day with 2 rather well informed hybriders? I guess I can look at the bright side......I have a set of B18B cams(better flow) and springs(newer and stiffer), that i'll be able to swap in at the same time

~steven :'(

 

I've never managed to replace a headgasket by myself... never had to yet, anyway (though my time is coming; I'm leaking oil). Were you smoking oil from under the hood or from the exhaust?

Anyway, I managed to pull the valvecover and remove the rocker assembly from a D16A6 in about an hour, and I'm not that much of a mechanic. A headgasket change isn't all that much more than that, from what I know... a few more bolts, etc.

 

My B18a compression readings were 195-195-185-195. That is, at least until i burnt an exhaust valve Your readings are still within paramiters, but they are a little low. Before i tear off the head, i would do a compression test after the car has been sitting all night. This gives a chance for the oil to drain off the rings, and it will tell you more acuratly how well they still seal. Also, check the antifreeze for signs of oil. Water smoke is whitish, and oil smoke is blueish. Also, a headgasket will cause you to overheat due to combustion leaking into the coolant. My B18 used to smoke too, but it was due to worn valve seals. Do yourself a favor and take the time to diagnose, so you can take care of the right problem the first time. When you go to take the head off, leave the intake manifold connected to it, and just make sure you unbolt the bracket on the underside of it. Email me with any other questions you have, as i've got a little experiance with B18as. Oh, and MAKE SURE you re-tourqe the head gasket after a few hours of running.

 

your compression numbers are at the low end of the spec for the LS but not terrible. The smoke you describe sounds like coolant and the leak between #3 & 4 sounds logical. Changing the gasket isn't too hard if you have the necessary tools, time, patients, and an extra set of hands.

It should take you and afternoon to do it. Go for it.

Mike

 

I dunno what to do. Now I know the hole in the head gasket is somwhere around cylinders # 3 and 4. that acounts for the plumes of white smoke I get intremittantly and the lower compression on those 2 cylinders. B18as should have around 185~190 right?

Think I ought to just hone my cylinders too? OR will replacing the head gasket and having a valve job done be good? I do want the best out of my motor. I plan on going turbo soon. my motor does have about 90~100K on it.....

 

Well your compression test has alot to do with air density and How many times you crank the motor over I am at 5200 feet above sea level and crank the motor over 4 times. On my B18C5 with 22,000 miles I pull 185 across the board with a leakdown of 1 percent or less.