Main IndexAuto Repair Home Search Posts SEARCH
POSTS
Who's Online WHO'S
ONLINE
Log in LOG
IN









Problems after Gasket repair...Help me..


Search for (search options)
First page Previous page 1 2 Next page Last page  View All



P0E2005
User

May 15, 2010, 8:46 AM

Post #1 of 28 (2858 views)
Problems after Gasket repair...Help me.. Sign In

1994 Pontiac Firebird 3.4 V6

I overheated it a while back and Got Bad compression...and White (Antifreeze) Vapor outta my tailpipe...So I knew it was either Cracked head or Blown Head Gasket...a buddy and I tore the engine down to the heads and replaced the head gaskets....Rebuilt the engine...Fired it up and let it runo for a while..and no overheating or White smoke yet...So Hopefully we fixed that issue..

However we created a new one...I am getting an ominous tapping noise from what I believe is a lifter not catching...It's Tapping while running and a really rough Idle...We ran a compression test and they all ran around 150-180..Except for one that registered a whopping ZERO on the compression test....So were assuming it's something wrong with the lifter...Now we have to tear it down again...Ugh...

My question is anybody have an Idea what we might have done to cause this and what we have to do to fix it?


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

May 15, 2010, 9:56 AM

Post #2 of 28 (2855 views)
Re: Problems after Gasket repair...Help me.. Sign In

Ideas: If you can get that cyl to TDC, blow air in and see where it comes out. Exhaust, intake, or combustion chamber as seen thru oil cap being off.

Could be this engine uses two different length push rods and one valve can't shut. Trouble is if that's the case it may have bent the valve or more damage.

ZERO is zero so you should find where air is going and that's what isn't tight.

If needed, remove valve cover and watch valves move.

I'm guessing by eye the head looked fine but it should have gone out for a machine shop inspection or repair if needed,

T



Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

May 15, 2010, 10:15 AM

Post #3 of 28 (2850 views)
Re: Problems after Gasket repair...Help me.. Sign In


Quote
Could be this engine uses two different length push rods and one valve can't shut. Trouble is if that's the case it may have bent the valve or more damage.

Tom probably hit the nail on the head right there.

Remove and check the pushrod lengths..

The intake pushrods are color-coded orange and are 6 in. (152mm) long.
The exhaust pushrods are color-coded blue and are 63/8 in. (162mm) long.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



(This post was edited by Hammer Time on May 15, 2010, 10:17 AM)


P0E2005
User

May 15, 2010, 10:23 AM

Post #4 of 28 (2844 views)
Re: Problems after Gasket repair...Help me.. Sign In

We will Check the Push Rods...But when we pulled them we kept them all with their appropriate Rocker arms in order...I don't think Over Torqueing the Nuts on the Rockers could cause this right?

And I know we should have sent the Heads out but money is tight (IE why we are doing this ourselves lol)

And the head isnt really the issue now...It's that Cylinder and Lifter...Maybe we got some dirt in it or something?...I guess I'm going to have to tear it back down and look at it...right?...

And the failing lifter would cause zero compression correct?


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

May 15, 2010, 10:30 AM

Post #5 of 28 (2839 views)
Re: Problems after Gasket repair...Help me.. Sign In

Yes, they are adjustable so being too tight will definitely make it miss and lose compression. It could prevent the valve from closing all the way. If it wasn't pumping up it will usually not totally lose the cylinder, just rattle a bit and not run smooth.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



P0E2005
User

May 15, 2010, 10:34 AM

Post #6 of 28 (2835 views)
Re: Problems after Gasket repair...Help me.. Sign In

We had a torque wrench and the Manual put it in inch pounds instead of foot pound...and I'll admit the day had grown long and bellies full with beer...and our conversions may have been off....

It's tapping something fierce...really rough Idle....and it showed zero compression...

Maybe we over torqued it...or under


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

May 15, 2010, 10:43 AM

Post #7 of 28 (2833 views)
Re: Problems after Gasket repair...Help me.. Sign In

These rockers aren't supposed to be torqued. They are adjustable.
Back them all off and start over

Here is the procedure


ROCKER ARM AND PUSHROD ADJUSTMENT

  1. Engine should be in number 1 firing position. This may be determined by placing fingers on number 1 rocker arms as crankshaft assembly is rotated. If valves are not moving, engine is in number 1 firing position. If valves move, engine is in number 4 firing position and should be rotated one revolution to reach number 1 position.
  2. With engine in number 1 firing position, following valves should be adjusted: Exhaust - 1, 2, 3 Intake - - 1, 5, 6
  3. Tighten adjusting nut until there is zero lash + one (1.0) turn . This can be determined by rotating pushrod while turning adjusting nut. When lash has been removed, turn adjusting nut in one (1.0) turn (to center lifter plunger).
  4. Crank engine one revolution. This is number 4 firing position. With engine in this position, following valves should be adjusted to zero lash + one (1.0) turn : Exhaust - 4, 5, 6 Intake - - 2, 3, 4




~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



P0E2005
User

May 15, 2010, 11:06 AM

Post #8 of 28 (2828 views)
Re: Problems after Gasket repair...Help me.. Sign In

Wow that was incredibly detailed...Thank you...

The book said tighten until there is no play (the same as lash I suppose...What exactly is lash?)...and then 3/4 to 1 1/2 turn but didn't walk through the firing order like that...


re-tired
Veteran / Moderator
re-tired profile image

May 15, 2010, 11:15 AM

Post #9 of 28 (2823 views)
Re: Problems after Gasket repair...Help me.. Sign In


In Reply To
Wow that was incredibly detailed...Thank you...


Hammer has been known to do that . He can't help himself.





LIFE'S SHORT GO FISH


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

May 15, 2010, 11:17 AM

Post #10 of 28 (2823 views)
Re: Problems after Gasket repair...Help me.. Sign In

"0" lash means when the pushrod first contacts the lifter without depressing it at all. Then you go an additional turn. That places it right in the middle of the lifter piston's travel. You have bottomed out every lifter.
You have to either follow the firing order or do it with the engine running. The cam has to be completely off that cylinder to find zero lash.
This is an important and critical adjustment.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



(This post was edited by Hammer Time on May 15, 2010, 11:20 AM)


P0E2005
User

May 16, 2010, 9:13 AM

Post #11 of 28 (2806 views)
Re: Problems after Gasket repair...Help me.. Sign In

I will start working on it again next Sunday....My Buddy went out of town for a week...

He's not a mechanic..but he's been doing it all his life..and he knows what he's doing...It was just midnight before we were done..and we were rushing a bit to get it done because he was leaving the following day...

I dunno...If we over torqued the lifters would it be clicking?...Or just holding it open?...


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

May 16, 2010, 9:20 AM

Post #12 of 28 (2803 views)
Re: Problems after Gasket repair...Help me.. Sign In


Quote
He's not a mechanic..but he's been doing it all his life..and he knows what he's doing


Now, that's a bit of a conflicting statement.
If he adjusted those rockers with a torque wrench, I'm afraid he's not even close to knowing what he's doing.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



P0E2005
User

May 16, 2010, 9:24 AM

Post #13 of 28 (2799 views)
Re: Problems after Gasket repair...Help me.. Sign In

No that was my mistake....I'm the non mechanic...I don't know why I said that....my mistake...he didn't take a torque wrench to those...The Manual said till there was no play in the rod then 3/4 to 1 1/2 turn to tighten...

So I think that's ok...Now what the manual didn't tell is the order to go in which you have stated so I'm thinking that's our only option


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

May 16, 2010, 9:27 AM

Post #14 of 28 (2796 views)
Re: Problems after Gasket repair...Help me.. Sign In

He should have known that you can't adjust a valve if it's on high cam. That's pretty basic stuff.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



P0E2005
User

May 16, 2010, 9:32 AM

Post #15 of 28 (2792 views)
Re: Problems after Gasket repair...Help me.. Sign In

Well I guess he did not know that...we will have to give it a shot and pray it helps...I really can't lose the car right now..lol...I know it's never a good time for this to happen...

But now is really....not a good time...

Now when you say place finger on Rocker to determine which position were in (and I'm sorry for asking remember..I'm great with computers but horrible with cars) you mean prevent the rocker from moving?


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

May 16, 2010, 9:38 AM

Post #16 of 28 (2788 views)
Re: Problems after Gasket repair...Help me.. Sign In

Your just feeling to see if the rockers are moving at all when the engine is rotated slowly to verify it's on #1 compression stroke because it doesn't have a timing mark. Your holding a slight pressure on the pushrod side to determine if the cam is pushing on it of not.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



P0E2005
User

May 16, 2010, 9:43 AM

Post #17 of 28 (2785 views)
Re: Problems after Gasket repair...Help me.. Sign In

ok...and if no movement...then adjust accordingly..and rotate to number 4 and repeat...

For reference sake...if this did not correct the issue?..plan b?


nickwarner
Veteran / Moderator
nickwarner profile image

May 16, 2010, 9:51 AM

Post #18 of 28 (2782 views)
Re: Problems after Gasket repair...Help me.. Sign In

He doesn't mean keep it from moving, he means see if it moves. If you are on TDC of the compression stroke, the intake and exhaust valves will be shut (thats how you make the compression). If they move, then obviously the cylinder isn't on compression stroke. It must be adjusted when the cam isn't moving the valve up. Thats why he gave you the procedure for this that is so specific.Its not a hard job to do, but attention must be paid to do this exactly as written, not kinda sorta in a hurry it'll probably work. Hopefully this will fix the trouble. As stated earlier, it would've been good to have the head checked out. Its less money than you might think to get them cleaned up and checked for cracks and warpage. Just 2 weeks ago I had a Grand Prix with coolant in the oil, and I told the owner the heads should be checked. He said he didn't want to spend the money. He drove about 50 miles and was back with the coolant in the oil. And the verdict was..... cracked heads. So he got to pay me twice to do the same job, got to buy 2 sets of expensive gasket, and got to be without his car for a week. I hope this doesn't happen to you, but keep it in mind for future cars.


P0E2005
User

May 16, 2010, 10:13 AM

Post #19 of 28 (2778 views)
Re: Problems after Gasket repair...Help me.. Sign In

I could take a pic of the gasket and post it..see what you guys think...but I didn't know how much it would cost to get the heads tested...

But I do know you need to send them to a reputable machine shop...My father said he has never sent off or heard of anyone sending off heads NOT coming back with the diagnosis of something wrong...


nickwarner
Veteran / Moderator
nickwarner profile image

May 16, 2010, 12:02 PM

Post #20 of 28 (2752 views)
Re: Problems after Gasket repair...Help me.. Sign In

That doesn't mean all machine shops are crooks. When they get heads sent to them, its because there was a problem with the engine. So its no surprise when they find problems with the heads. Their job is to make the heads perfect so they will do as intended. Machine shops rarely get good heads sent to them because of this. Look at it this way, how many people in perfect health does a doctor see in his practice? They are only there to see him when there is a problem.


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

May 16, 2010, 12:53 PM

Post #21 of 28 (2746 views)
Re: Problems after Gasket repair...Help me.. Sign In


Quote
But I do know you need to send them to a reputable machine shop...My father said he has never sent off or heard of anyone sending off heads NOT coming back with the diagnosis of something wrong...


What the hell did you expect. Of course a head that had been overheated and abused is going to have a problem and your asking the guy to find it. I'm not a machinist and I can pretty much guarantee it at least needed to be resurfaced.

I really get tired of the "everybody in the car business is a crook" crap.
You keep listening to these clueless people and your problems are only going to get worse.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



(This post was edited by Hammer Time on May 16, 2010, 12:56 PM)


P0E2005
User

May 16, 2010, 12:57 PM

Post #22 of 28 (2738 views)
Re: Problems after Gasket repair...Help me.. Sign In

Good Point Nick...

And Hammer...calm down bro..I didn't say everyone was a crook...I'm saying that a minor imperfection in my heads isn't the same as a life threatening crack...and I just didn't want to buy new heads if I didn't have to...

And the people I am talking to and dealing with aren't clueless man...My buddy has done this all his life...and has replaced the heads and gaskets to his cars a few times and to others many times...If we knew what the problem was I wouldn't be here...but we're not clueless......

I have a question though if your still willing to answer hammer....I asked my buddy (the clueless one)...about tightening them in your order and he said their Hydraulic lifters and the timing isn't adjustable so he did not think that they needed to be tightened in any specific order...

Is that true?...Or do we still need to go through your process?


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

May 16, 2010, 1:00 PM

Post #23 of 28 (2733 views)
Re: Problems after Gasket repair...Help me.. Sign In

No, the timing is not adjustable but the lifters are.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



P0E2005
User

May 16, 2010, 1:00 PM

Post #24 of 28 (2730 views)
Re: Problems after Gasket repair...Help me.. Sign In

once again....not disputing what you said...we are asking YOU


P0E2005
User

May 16, 2010, 1:02 PM

Post #25 of 28 (2728 views)
Re: Problems after Gasket repair...Help me.. Sign In

ok so even though their not (and I'm quoting him) "manual lifters but rather hydraulic"...we should still do it this way?






First page Previous page 1 2 Next page Last page  View All
 
 






Search for (options) Privacy Sitemap