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OhioProstar
07-10-2005, 09:42 PM
Ok gear heads, this week I had a sparkplug melt on the driver's side bank. I replaced it with AC Delco MR43Ts and everything seemed fine again. On the way back to the dock experienced the same issue. The engine runs cool with good oil pressure. Could the water jacket be bad around just that cylander or do I have a bigger issue?

JimN
07-10-2005, 10:09 PM
Look at the PCV valve and the hose going to the intake manifold- chances are, it goes to the #8 cylinder runner. This needs to be changed so it goes to the base plate of the throttle body, replacing the barb with a plug for the original hole. The way it was made, #8 runs too lean and you can burn the plug(or worse). Make sure the PCV valve is clean and operating properly.

NeilM
07-10-2005, 11:40 PM
Man, the depth and breadth of your knowledge just blows me away! :worthy:

JimN
07-11-2005, 12:13 AM
It's nothing special, I just happen to have a Rain Man-like memory for some things and the only lean-burn issue I remember is the one on the older TBI models with the PCV valve gong in through the #8 runner, causing the plug to burn.

Double Overhead
07-11-2005, 01:01 AM
It's nothing special, I just happen to have a Rain Man-like memory for some things and the only lean-burn issue I remember is the one on the older TBI models with the PCV valve gong in through the #8 runner, causing the plug to burn.

I was going to say the same thing

Kell
07-11-2005, 01:10 AM
Make sure the PCV valve is clean and operating properly.Jim, so how would you suggest cleaning the PCV valve and insure it is operating properly. I went and tried to pull mine out of the valve cover, and there must be some trick to removing it. It will turn, but I can't pull it out. It does not appear to be threaded. Thanks.

jimmer2880
07-11-2005, 07:18 AM
It's nothing special, I just happen to have a Rain Man-like memory for some things and the only lean-burn issue I remember is the one on the older TBI models with the PCV valve gong in through the #8 runner, causing the plug to burn.

:worthy: ... just :worthy:

BriEOD
07-11-2005, 09:11 AM
It would be nice if we knew where to send all this beer money!!

JimN
07-11-2005, 08:19 PM
If it doesn't want to come out, the rubber grommet is probably pretty hard and may need to be replaced. The PCV is cheap enough, so it's better to get a new one if you don't remember changing it before.

Brown paper bag, unmarked bills, in a van down by the river.

6ballsisall
07-11-2005, 08:20 PM
:worthy: ... just :worthy:


ummm.... you couldn't have said that better jimmer, JimN you are da man' :worthy: :headbang:

LakePirate
07-11-2005, 09:00 PM
:worthy: Many times I have asked myself where would we be without JimN

Thrall
07-12-2005, 12:41 PM
You didn't specify if it was #8 or not, but if it was #2, 4,or 6 cyl, you may have a leak in the intake manifold gasket causing a lean burn on one hole as well. If it was bad enough to cause a plug to melt, you'd probably have substantially lower vacuum and idling problems as well.

OhioProstar
07-12-2005, 06:40 PM
Good point Thrall...I haven't check under the hood yet for JimN's PCV advice, but a leak in the intake manifold gasket might make sense if not. I will have to check it out tonight and take some pics. I have noticed what I thought was a stuck lifter (tapping sound) when I would run WOT but NOT under 3500 RPMs, but I am starting to think it is more of an issue of running lean.

OhioProstar
07-21-2005, 12:46 PM
Okay...I have been traveling for work to much and just got enough time to look under the hood.

The PCV valve does come from the intake manifold to a spot between the #8 and #6? cylinders. The PCV is not clogged but rattles around quite a bit. Can I just replace the PCV and see if it fixes the issue or if not what is the process of relocating the intake hose to the throttle body?

6ballsisall
07-21-2005, 12:59 PM
I have noticed what I thought was a stuck lifter (tapping sound) when I would run WOT but NOT under 3500 RPMs, but I am starting to think it is more of an issue of running lean.


Lean is mean but don't let it tear apart your machine!! :purplaugh

JimN
07-21-2005, 10:22 PM
The PCV should rattle when you shake it but it has a spring inside that keeps it from opening completely at low RPM. As long as it doesn't stick open or closed. Ideally, the plate below the throttle body should be replaced by the new style and the hole in the manifold plugged(common cast NPT plug). This makes the crankcase gases go into the intake without favoring any particular cylinder.

When you said "between #6 and #8", did you mean on the raised area close to the rear of the manifold? This would be the #8 runner, and this is the cylinder that has been problematic at high temperatures with low octane or old gas. If you can post a photo, that would help, too.

OhioProstar
07-22-2005, 09:43 AM
The burnt plug was the one right behind the #8.