A&Q about 350Z
Q:
I have a 1988 Buick Century Custom that had blown out the two center spark plugs (2.8l v6) after I replaced the plugs and wires.
I then changed the plugs back to bosch and was having a bucking issue. After one of those spark plugs had blown out, it was realized that I needed a helicoil insert. This was something that I was not going to even try to attempt.
So I brought the car over to a local mechanic and the car ran just fine with 1 spark plug missing. Just a little loud thats all. They installed a helicoil in the bad plug and checked all the other plugs. Said all was fine except that it ran really rough.
They said it might be clogged fuel injectors, so I dropped some tekron cleaner in the tank and let it run for 1½ hour with no improvement.
The next day, I ended up replacing one of the coil packs due to skipping spark issues. Still had serious problems. When I removed the helicoiled spark plug, the cyclinder had slapped the gap shut on it and marred the metal on the gapper and the bottom of the threads.
Now the garage is telling me that I definately need a reconditioned head and that will cost ~$900.00 to do.
Is there ANYTHING that can be done to fix this problem?
Who should be fotting the bill here?
The car is still good other than it obviously needs new shocks.
What should I say and who should I go to?
Thanks in advance!
A:
Lucky you I actaully worked for a Helicoil design/selling company (
). More than likely the garage used a standard tanged insert. With this, there is actually a small metal tab that is located on the end of the insert itself. A driver grabs that metal to twist the helicoil in, when its reached the desired depth, you break the tang, and retrieve it. Let me tell you some concerns that I have about your post--
1. In order to install the helicoil, the diameter of the hole must be tapped larger to compensate for the helicoil. With this come metal shavings from the tapping of the hole. The fact that your mechanic did not remove the head (he should have charged you for a head gasket among a couple of other things) is concerning.
2. The tang thats broken off, (It is possible the insert was tangless, but not likely) would also be broken into the chamber, this could have been taken out with a magnet, but if was left inside would cause damage.
3. The most concerning thing to prove they didn't take the head off, they installed the helicoil too deep. This allowed the spark plug to be installed just as deep causing interference with the piston.
I would blame the mechanic for not properly installing the insert. They installed it too deep causing other problems. They should be footing the bill for the reconditioned head. You payed them to correctly install the insert, which they obviously failed to do. This resulted in further damage, and instead of being a decent business and accept the blame, they are trying to foot you with an additional repair bill. I would very politely tell them your findings and why it happened and what work you had them do. At first be polite, I urge you to refrain any anger. I know you may be upset, but if you go in there trying to raise hell, people will be less likely to help you. If they don't offer to fix the problem, then raise hell. Go to the BBB (Better Business Bureau) report them, and may be follow suit in small claims if it comes to it. Its definetely not a bill you should have to pay for. Don't have them do any more work for you, if you do have the head reconditioned, go to a different mechanic and hand the old one the bill.
One question I do have, spark plug threads just don't strip under normal driving conditions, did you perhaps cross thread a plug on re-install/replacement? (I think this is the likely reason) For future reference, when installing spark plugs, install them by hand at first, using the extension on top of the socket if necessary, turn that by hand, do NOT grab the first couple of threads with a wrench this leads to cross threading, and eventually this headache that you're now suffering. Sorry for the late advice, but best of luck with your situation!
A:
Some things to consider:
They may say that you removed/installed a plug in the helicoiled hole and caused that problem.(Although the rough running immediately indicates the plug may have been installed too deep initially)
It may be possible to remove the old helicoil if damaged and replace it without removing the head. They would need to look inside with a borescope to see what kind of damage occurred if any.
It does sound like they should be responsible and pay for the damages. You should give them first option to try to make it right. If they won't do it, and you are willing to go to small claims court to settle and put out some extra money, you can take the car somewhere else, have it repaired and then sue them for that repair too. Just make sure you have some documentation that they were offered a chance to fix it first like a letter.
A:
I have decided to put the car up for sale. If you are in NY state and have the ability to replace the head or cob this back together, you are more than welcome to contact me. It would make a great parts car as well.
A:
Excelsior, its an automatic I presume?
A:
It is.
2.8l
Buick Century Custom
new brake lines last year
new battery
new Mass Airflow Sensor
140k miles
Brown/Tan
has a few dents from tree branch falling.