View Full Version : Clunk!
Don Nelson
04-19-2007, 03:36 PM
I recently took my '90 out of winter storage (garaged), had the oil and filter changed (Mobil One), and fluids checked. I do this every year. It has 45k on it and ran a little hot last year, so had the hoses checked and raditor flushed out. That helped a lot and for the next couple days it ran cool and well. The other day it started running rough and after a mile or two, I noticed that the pass. side exhaust was white at idle, and "service engine soon" light came on. I pulled into a parking lot and shut it down. After letting it cool off, I turned it over and it did not start. Before calling the tow truck, I tried it one more time and...CLUNK! It appeared to seize up! The dealer got it started and he reported that it smoked a lot and speculated that it may be a head gasket, cracked head, or a warped head. He was afraid to work on it, so it is now in my garage. I have never had any problems with this car. It has never smoked (or used any tobacco products), nor has been particularly "clacky". I am not a mechanic, but I would think that if it is something this severe, it would have been indicated beforehand. Oil pressure has always been good, and except for the high temp (never exceeded normal operating temp), it has never shown any signs of distress. I have checked the oil and antifreeze and there does not appear to be any cross-over of fluids. My question: What should I check before taking this thing apart?
Jeffvette
04-19-2007, 03:39 PM
Drain the coolant and oil. Look for cross contamenation. Pull spark plugs and crank motor over as well. See if you get any fluid coming out (make usre you cover everything).
If anything out of the above three options the service guy gave you, it will be a head gasket failure.
Give me a call if you need any help. BTW what part of Anchorage do you live? I used to live off New Seward and 36th.
Don Nelson
04-19-2007, 04:10 PM
Okay. I will give that a try.
I live on Lake Otis, down by Merrill Field.
BTW...My girlfriend and I are headed to Seattle (for the weekend) in June. Looking forward to some golf...any suggestions?
Jeffvette
04-19-2007, 04:14 PM
When in June are you coming?
Don Nelson
04-19-2007, 04:20 PM
I think around the 1st. It's an award she received from her employer, so I don't have much to do with the arrangements...just along for the ride!
Jeffvette
04-19-2007, 04:27 PM
Plenty of things to do. June is a pretty good time to be here. A few hot streaks, but for the most part the days are comfortable.
Z Factor
04-19-2007, 11:46 PM
Hello Don, glad to see you posting :handshak:
I would take Jeff's advice, and don't run it until you check the fluids, plugs etc. You don't want a hydro-lock.
Keep us posted on your progress and feel free to ask for more help.
As to visiting Seattle in June,,,hmmm June + Seattle = RAIN
Actually ,,,, any month + Seattle = RAIN :mrgreen:
When you have a moment zip over to this thread and cast a vote for Alaska.:thumbsup:
http://zr1netregistry.com/forum/showthread.php?t=1009
:cheers:
flyin ryan
04-20-2007, 01:00 AM
i would do a leakdown test if you don't find something obvious. have never done one on an LT-5 but it has to be as easy as it gets. pull the plugs & bring the hole your working on to TDC. i'm not sure if the damper is marked in 90° incriments or not? if not slide something down the spark plug hole & by turning the engine over by hand you'll be able to get real close. then have at err'. can walk you through it in more detail if you need, no problem.
Don Nelson
04-20-2007, 03:38 PM
Okay...the plot thickens...
I pulled one sparkplug to test the compression, but when I turned the engine over it locked again...so, I pulled all the spark-plugs and turned it over again. This time the second cylinder on the 2nd (passenger side) bank spewed fuel all over the place! After cleaning that mess up, I tried it again with a clean rag over the spark-plug hole and checked the rag (after it blew against the wall). It's pure fuel, but a lot of it. BTW: There does not appear to be any cross contamination between antifreeze and oil.
So...is this a fuel injector problem...fuel rail...throttle-body?
Jeffvette
04-20-2007, 03:42 PM
Sounds like you may have an injector stuck wide open. Which can cause hydro-lock and be very bad. Look at replacing all the injectors.
Z Factor
04-20-2007, 05:37 PM
So...is this a fuel injector problem...fuel rail...throttle-body?
The good news is that it is probably a leaking or stuck injector. The bad news is that it is probably a leaking or stuck injector.:mrgreen:
In all seriousness, you will have to at a minimum replace the one faulty injector. That will be the least expensive route for you. However, you should know that the other injectors could start to leak (if they aren't already) or get stuck open. Since you are in Alaska and "not a mechanic" you will only want to do this job once since it entails taking off the plenum, fuel rails, etc.
So I would recommend that you replace all your injectors now rather than hope the others will last for a few more years. Keep in mind that you can just replace the faulty ones and may not have a problem with the others for a while. But for your peace of mind and possible cost savings if you have someone else do the job, replacing them all will probably be your best bet.
:cheers:
tccrab
04-20-2007, 06:58 PM
The good news is that it is probably a leaking or stuck injector. The bad news is that it is probably a leaking or stuck injector.:mrgreen:
:cheers:
:iamwithst
I predict a plenum pull in your very near future.
I'm sure one of us wouldn't mind flying up there for a weekend to help you with the job, providing of course a hunting or fishing trip could be added to the package...
Ccmano
04-20-2007, 08:04 PM
I'd be very careful here. While the injector is no doubt the problem, we don't know if the hydrolic lock that has already happened caused any problems. You don't want to cause any more damage by installing new injectors and lighting her up only to find you had a bent rod that's now tearing up something else.
This engine should really be looked at by somebody knowlegeable (if you aren't) I would at least turn it over by hand with the plugs out and see if anything is hitting anything else. I would also measure TDC height on the one with the problem and compare it to a good cylinder.
While I haven't experienced it on these engines, I've seen Benz engines that have hydrolocked and caused a minor bend in the rod, only to cause more serious damage later on, and it doesn't take long!
Take it slow...:pray
Hans:cheers:
Don Nelson
04-20-2007, 09:21 PM
Thanks for all the advice!
One last thing: By "replace all of the injectors", does that mean both primary and secondary injectors. Can I just replace the primary, and if so (and I know the answer here), can I use an aftermarket injector or should I stick with OEM?
Lots of good advice given. I might add that you should change the oil before running the engine. Fuel diluted oil can seriously damage rod & main bearing, cam journal bores, etc.
All of the injectors means primary & secondary. Leakers don't discriminate.
OEM: are very high priced.
RC: injectors are expensive, but worth it.
Accel: A relatively recent test of Accel injectors which are easily modified, have shown good promise and are the cheapest route to go. Search the ZR-1 section (archives) for Accel injectors to see the full story. Jeffvette will probably know the full story on them.
flyin ryan
04-21-2007, 03:26 AM
Okay...the plot thickens...
I pulled one sparkplug to test the compression, but when I turned the engine over it locked again...so, I pulled all the spark-plugs and turned it over again. This time the second cylinder on the 2nd (passenger side) bank spewed fuel all over the place! After cleaning that mess up, I tried it again with a clean rag over the spark-plug hole and checked the rag (after it blew against the wall). It's pure fuel, but a lot of it. BTW: There does not appear to be any cross contamination between antifreeze and oil.
So...is this a fuel injector problem...fuel rail...throttle-body?this is a best of a worst case scenario. drain the oil to see how much got past the rings. you might have got away very lucky. and that's O.K.
Z Factor
04-21-2007, 01:46 PM
Thanks for all the advice!
One last thing: By "replace all of the injectors", does that mean both primary and secondary injectors. Can I just replace the primary, and if so (and I know the answer here), can I use an aftermarket injector or should I stick with OEM?
You can replace one or all, but if you only replace the faulty one/s, use the same brand (i.e. OEM with the same, or RC's with the same). I have heard of some people replacing all the primaries with one brand and having different secondaries, which seems to have worked out. However do not mix different injectors within the group as they could have different flow rates and spray patterns.
Though all of them can have a problem down the road, there are several people who have just replaced a few or one group (i.e. primaries). The only issue there is you can put everything back together and within days another starts to leak.
:cheers:
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