Rebuilding head

[FLIPTION]

So my vacuum has been -10inches since my timing belt change. After a couple boost leak tests (one by me, another by shop), my mechanic says the leak may be coming from the valves which may be bent. He quoted me $700 for new valves, head gasket, 3 angle valve job, and will even throw in a set of ARP studs. Is this a good deal or shall I go another route (ie; head swap if i can find a 1g head for cheap)? My car is still pretty much stock. I will upgrade the turbo once this leak is diminished. Any thoughts?

Allan

 

[No_Skillz]

You should make sure that your valves are bad before such an expensive job. Please describe how you did your boost leak test and what the results were. Also, doing a leakdown test will help you figure out where your air is escaping from.

 

[absolute_DSM]

Definately make sure the head is the problem. Check your timing first to make sure its on.

If you do end up havin to tear it all down, tear off the head and pull the valves yourself. That will take care of that high bill.

 

[FLIPTION]

Does pulling off the head consist of taking off the timing belt and such? Is it a hard job?

 

[FLIPTION]

When I first got my timing belt changed, this mechanic who never worked on a DSM messed it up. He was off a couple teeth and kept cranking it. Never got it to start. . so I got another mechanic to get it to start, sure enough he did. He told me that the teeth were off and said it was very close to having the valves make contact w/ the pistons. The car never ran the same since (bad idle). I'm not exactly sure if this was when the vacuum started leaking. Since then my vacuum kept getting worse.

I did a boost leak test using a boost leak tester. Could not find any significant leaks that would cause that bad of a vacuum leak. I paid this reputable shop $90 to diagnose the car because I just could not figure it out. They could not find anything as well. I was there the whole time to watch them to make sure they were doing their job correctly. My compression came out to be 155, 145, 145, 155. I explained to them about my previous timing belt job which had them come to the conclusion that it's the top end (possible bent valves) that the valves weren't seating correctly. So the owner recommended I rebuild the head.

Does pulling off the head consist of taking off the timing belt and such? Any more input?

Thanks guys!

 

[laserspeeddemon]

Yes, you have to undo the timing.

 

[95blackGsTurbo]

You don't HAVE TO undo the timing but it's recommended unless you know the proper way to do it. RRE did a write-up on an EVO that is essentially the same thing. You make a tensioner tool to take all of the tension off of the hydraulic tensioner and zip tie the belt to the gears and line it all up and take the gears off of the ends of the cams. Just make sure the belt doesn't come off the crank pulley. Same a TON of time though. I would do a leak down test to ensure that was your problem first though.

 

[daren_p]

Did the low vacuum issue happen as soon as you had the timing belt done? If so is the person who did the job taking care of the bill as they probably caused your issue? Have you verified all the timing marks are lined up properly? If you are off a tooth or two somewhere, this can cause low vacuum. Have you done a compression test? If you haven't check these two things first. If the compression test checks okay, then the timing belt probably wasn't installed correctly.

Edit: Sorry missed one of your posts, compression test numbers are abit on the low side (though still within the service limit). I'd do a wet compression test to verify the rings are good & then from there go to a leak down test.

 

[90laserRSfwd]

Do a leak down test

 

[motomattxxx]

You dont have valve problems with compression numbers like that look elsewhere. Any good mechanic would not have to "throw in" parts to sweeten the deal, he should be swamped with work already and not making deals to get work.