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Pull block or just replace gaskets?

  • Thread starter Thread starter TheUser
  • Start date Start date Dec 26, 2003
T

TheUser

Active Member
Jul 25, 2003
1,859
1
36
Springfield, MO
Dec 26, 2003
#1
  • Dec 26, 2003
  • #1
I'll try to make this short and sweet.

Here's my dillemma:

I have the car in my sig, supposedly rebuilt 5000 miles ago. I have no documentation, however, but it probably was. I pulled the heads because of low compression to find some bad head gaskets. My dillemma is: Do I replace the head gaskets with new ones and bolt the stuff back on OR, do i go ahead while I have the heads and everything else off and pull the block, have it inspected, replace oil pump and driveshaft, new rings, bearings, etc.? Would it be worth it?

On one hand, I don't want to spend more money than I have to, but on the other hand, I wanna do it right the first time. I really can't be sure what I have unless I pull the block and replace things and have it inspected.

Also, JadeFalcon said Cometic makes good gaskets, so i'm considering those, but I don't want TOO GOOD of gaskets and end up breaking my motor under boost.

All in all, i'm having fun and things are going very well, but I'm just looking for some advice from people who have more knowledge/experience than me. Without you guys, the heads and intake would prob. still be on that car w/ blown head gaskets right now. Thanks!

I can post pics of the gaskets if someone wants to see them.

Oh yeah, what causes the chamber tops on the heads to be all rusted? #2 on the pass head and all of the drivers side head cyc. tops are rusted and about 1/4 around the top of the cyc. walls are rusted as well. Is that just from the faulty gaskets?
 

mike keirstead

New Member
Aug 6, 2003
1,121
0
0
ROLLING A JOINT
Dec 26, 2003
#2
  • Dec 26, 2003
  • #2
Inspect the top of the cylinder wall. If there is a ridge you can see or feel then you may want to have it looked at. If it dosnt use oil and its knock/ticking free then chances are you would not need a rebuild. If it was not rebuilt then if you have the money it would be worth it to rebuild it. Thats just me. I just had mine rebuilt top to bottom with .040 over forged pistons and it was money well spent.
 

BigDaddyCee

Founding Member
Jan 1, 2000
1,404
0
0
Canada
Dec 26, 2003
#3
  • Dec 26, 2003
  • #3
If I was confident that the head gaskets were the sole problem for the compression loss then I would only change them. Depends on your pocket book and the level of confidence you have in the previous rebuild how much further you should go? Also you need to think about down the road how you will feel if something goes wrong if you don't do the proper job now. Question? what led you to change the head gaskets in the first place was it billowing white puffy smoke or what. Did you do a compression test before?
 
T

TheUser

Active Member
Jul 25, 2003
1,859
1
36
Springfield, MO
Dec 26, 2003
#4
  • Dec 26, 2003
  • #4
Since blown head gaskets on blower applications is pretty common, I think that might be the only problem. I'm still waiting for idea's, but i'll prob. just have the heads cleaned up and valves replaced, replace head gaskets, get some ARP head studs and a fuel pressure guage and bolt it back up. It quit running, wouldn't start and did compression test, which came back that 1 cyc. had around 160 psi, one had around 110, one had like 90, four had around 40 psi and then one was around 10 or so. The gaskets are split between a couple cyc., on each side, so I heard that will spread to the other cyc.
 

IndyBlk5.0

New Member
Nov 24, 2003
1,122
1
0
New Whiteland, IN
Dec 26, 2003
#5
  • Dec 26, 2003
  • #5
ouch!!!!!!!! i thought i had it bad.... if your running boost make sure you get reinforced head gaskets, aka metal ring around the pistons. or you will just have the same problem...
 

BigDaddyCee

Founding Member
Jan 1, 2000
1,404
0
0
Canada
Dec 26, 2003
#6
  • Dec 26, 2003
  • #6
If you have evidence that it was just the gasket like burn marks where the gasket was burned up between cylinders then O.K. Just make sure there is not another problem here too, like warped heads or nicks or scratches on the head surfaces that are causing your head gaskets to fail. Check the plane on the heads for flatness. As you said new head bolts are a good idea too. Old ones can get stretched when torqued down. Good luck.
 
T

TheUser

Active Member
Jul 25, 2003
1,859
1
36
Springfield, MO
Dec 26, 2003
#7
  • Dec 26, 2003
  • #7
the old gaskets DID have the metal ring! The a couple of the metal rings on the drivers side head are all torn to hell. That's what pushing 11 lbs of boost will do I guess!

Took the heads to get inspected/cleaned up and he said it would be best to mill them a little to make sure they're flat. I asked him about doing valve seals because I was told that's something I should do and he said if I do that, might as well do a complete valve job. I decided against that. The heads are supposed to be pretty new anyway.

If all goes well and I can get my parts in by new years day, i'll prob. get it thrown back together then

I can't wait to drive it...it's been down since June...didn't know what was wrong, then a shop told me bad rings and I think they were full of *****, but I didn't think that then, so now I finally got it torn down over christmas break. Either way, it's a blast.
 
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