CorvetteForum - Chevrolet Corvette Forum Discussion

CorvetteForum - Chevrolet Corvette Forum Discussion (https://www.corvetteforum.com/forums/)
-   C4 ZR-1 Discussion (https://www.corvetteforum.com/forums/c4-zr-1-discussion-50/)
-   -   28 years of waiting... (https://www.corvetteforum.com/forums/c4-zr-1-discussion/4180685-28-years-of-waiting.html)

Gonzo_65_L76 08-24-2018 11:22 PM

28 years of waiting...
 
At 20 years old, I was lucky enough to drive a 1990 ZR1 in late 1989. It was the first super-car I'd ever driven, and I swore I'd eventually own one... and here we are.

I was not looking for a ZR1, but one fell into my lap. A neighbor of mine sold me a 1991 ZR1 with 53k miles. That car has not been driven for 3-5 years, but does start and run well. I will be picking the car up on Monday and driving it the ~1/4 mile back to my house to get it up on a lift.

Beyond fluids... what's on the list of tasks I should be taking on before I start driving this thing the way it was intended? I do plan to drive this hard, and eventually track it. Any advice would be greatly appreciated.

Mike.

bb62 08-24-2018 11:43 PM


Originally Posted by Gonzo_65_L76 (Post 1597859484)
At 20 years old, I was lucky enough to drive a 1990 ZR1 in late 1989. It was the first super-car I'd ever driven, and I swore I'd eventually own one... and here we are.

I was not looking for a ZR1, but one fell into my lap. A neighbor of mine sold me a 1991 ZR1 with 53k miles. That car has not been driven for 3-5 years, but does start and run well. I will be picking the car up on Monday and driving it the ~1/4 mile back to my house to get it up on a lift.

Beyond fluids... what's on the list of tasks I should be taking on before I start driving this thing the way it was intended? I do plan to drive this hard, and eventually track it. Any advice would be greatly appreciated.

Mike.

What year is it? The 90-92 cars should have the injectors changed. The 93-95 cars don't have the same problem (today's ethanol affecting the injectors). I would change the gas (or run the old gas out) and check most of the important systems (brakes, etc.) to make sure they are working properly. If the tires are old - they need changing. Good luck.

Gonzo_65_L76 08-24-2018 11:45 PM

Sorry. The car is a 1991.

Interesting about the injectors. I'll plan on replacing those.

Mike.

mhobtr 08-25-2018 10:48 AM


Originally Posted by Gonzo_65_L76 (Post 1597859560)
Sorry. The car is a 1991.

Interesting about the injectors. I'll plan on replacing those.

Mike.

While you're doing that, you can remove the secondary throttle plates, or tie them open, and eliminate the headache with the failure of it's vacuum system.

Order gaskets and fuel rail O-rings from Jerry's before you start. He will help you get what you need. He has new injectors for sale also.

ccmano 08-25-2018 11:42 AM

Welcome to the club! Don’t forget to check in over at the ZR1.net forum. Your best resource for help with these cars is these two sites. The “search” function is your best friend for any question you may have. I guarantee whatever question you can come up with it’s has been asked and answered before.

Who will be smoging the car? You or the current owner? Don’t be surprised if it doesn’t pass. CA has been increasing smog requirements for years on older cars. It can be done but may require some tweaking. Again, run a search for CA and SMOG on both sites and get familiar with the issues.
Good to have you with us.
H
:cheers:

ghlkal 08-25-2018 05:57 PM

Congratulations, I'm sure you'll enjoy it!

Gonzo_65_L76 08-28-2018 11:31 PM

Ok. I went and picked up my new toy. The good news is that even though the owner hasn't driven the car in about 10 years, the car was driven about once a year by a nephew. The car also had a full tune-up and smog in Sept., 2016... about 50 miles ago. The car started right up and runs strong. I drove it ~1/4 mile to my garage where it's currently parked.

The biggest issue is that it's dirty... very, VERY dirty. A rat got into the engine bay and left a generous deposit of feces and urine on top of the engine. The exterior is covered in a very thick layer of dust. The interior is the only part of the car that's clean.

The question I have - Can I steam clean the engine? I can't see a danger with doing this, but thought I'd ask. It will make working on this thing far easier if I can clean it up first. Plus, it bugs me.

-Gonzo

ccmano 08-29-2018 10:50 AM

Do not under any circumstances steam clean the engine! Water in the valley of the engine can cause any number of electrical and electronic issues. Take your time and clean the engine manually. Use only mild soap and water on the plenum and cam covers with a damp rag. Any thing stronger can stain the plenum and cam covers even more. Take it slow. Use compressed air to blow out the loose stuff.

Post some pix, let’s see how she looks.
H
:cheers:

DRM500RUBYZR-1 08-29-2018 11:05 AM


Originally Posted by ccmano (Post 1597884286)
Do not under any circumstances steam clean the engine! Water in the valley of the engine can cause any number of electrical and electronic issues. Take your time and clean the engine manually. Use only mild soap and water on the plenum and cam covers with a damp rag. Any thing stronger can stain the plenum and cam covers even more. Take it slow. Use compressed air to blow out the loose stuff.

Post some pix, letís see how she looks.
H
:cheers:

:iagree:

DO NOT WET THE ENGINE!!!

Congratulations on getting the car of your dreams!!!
Dreams DO come true!
Check with folks here before venturing into the unknown, as many are always willing to offer guidance and suggestions, particularly when you have questions.
No need to take the arrows, as those before you have already scouted out the best way to get things done, and are quite willing to share and help.

Best of luck in getting the small stuff sorted out, and once done, prepare yourself for some major smiles!
:cheers:
Marty

mhobtr 08-29-2018 12:47 PM


Originally Posted by Gonzo_65_L76 (Post 1597882546)
A rat got into the engine bay and left a generous deposit of feces and urine on top of the engine. -Gonzo

If you found evidence of a rodent was on top of the engine, there is most likely a nest under the plenum. Need to pull the plenum and starter and clean everything out. Look for chewed wiring and vacuum lines.

While you have the starter out, you can drill the recommended extra drain hole under the starter. Search online for "GM Service Bulletin #92-307-6".

Gonzo_65_L76 08-29-2018 07:42 PM

Oh joy. Oh happy day.

Yes. there's evidence of a nest under the plenum. Not sure how they would get in there, but I see feces at the very least.

Is there a recommended shop manual for these cars? Removing the plenum looks simple enough, but if I go further, it would be great to have some docs. I have been going through ZR1.net forums. Good stuff, but would still love to have a shop manual if one is available.

Below are a couple pics of the car after moving it to my garage. I have a little work to do.

https://cimg9.ibsrv.net/gimg/www.cor...dd0b7202c0.jpghttps://cimg2.ibsrv.net/gimg/www.cor...a935bd8424.jpg
https://cimg7.ibsrv.net/gimg/www.cor...67f2721fb4.jpg

ccmano 08-29-2018 08:52 PM

The plenum pull is a right of passage in the Z community. Everyone gets to do it at some point, or pay to have someone else do it. Pretty straight forward really. Get yourself a factory FSM for reference. Remember, this engine is nothing like an SBC. Your going to have to learn a whole bunch of new stuff to work on this one. The sticky at the top of this forum posted by “Dynomite” Tech Info has just about everything you ever wanted to know. In this case start at post 105... for plenum pull info.

Here is the same sticky over on ZR-1.net forum.
http://www.zr1.net/forum/showthread.php?t=16778

Looks like a solid car. Should be awesome when you get it cleaned up.
Have fun.
H




Gonzo_65_L76 08-30-2018 01:21 PM

One bit of good news - I got a bunch of goodies with the car:
  • Original window sticker
  • Original box with leather ZR1 portfolio, ZR1 Video cassette, owners manual with ZR1 supplement and signed letter from president of GM (probably a stamp)
  • Original bill of sale from dealer
  • Original warranty information
  • Roadside assistance package
  • and a few other bits
Basically everything you come home from the dealership with got thrown into a box and saved for me.

My 6yo has informed me that I can now keep my '65. He's claiming the ZR1 for himself. He also wanted to know how much more go-kart time he needs before he can take it out for a spin. Luckily, I don't think they make pedal extenders for ZR1s.

-Gonzo

wfot 09-01-2018 09:09 AM

TO be more specific about washing the engine... the starter is located inside the vee under the plenum. there is an undersized drain hole from the factory, that clogs and if the engine gets water in the vee, it will drown the starter. 93 - 95 they made the hole larger, but it is still NOT a good idea. FWIW...

zrc3john 09-01-2018 12:35 PM

Oh man, looks a tad bit dirty on the underside....Never the less I would get her on all four jack stands,wheels off and take my time cleaning it...

Take photos along the way when you remove plenum......Underneath there are some vacuum hoses that you can snap photos of with your camera before disconnecting ......The plenum will lift off enough before you disconnect everything so you can snap a shot....

May as well change the wires and inspect coil packs for rust when plenum is off....You can pick up aftermarket wires for a decent price...

Good luck..

Gonzo_65_L76 09-01-2018 06:38 PM

Jack stands...? What are those? ;)

Already up on the lift.

Anyone have the set of pics that went with the eliminations post here? Specifically, I'm looking for pics associated with post #4 - "Eliminating the TB Coolant System".

Before I do that... is there an easy way to see if my TB Coolant System has already been eliminated? I assume not.

-Gonzo

zrc3john 09-01-2018 06:46 PM


Originally Posted by Gonzo_65_L76 (Post 1597906523)
Jack stands...? What are those? ;)

Already up on the lift.

Anyone have the set of pics that went with the eliminations post here? Specifically, I'm looking for pics associated with post #4 - "Eliminating the TB Coolant System".

Before I do that... is there an easy way to see if my TB Coolant System has already been eliminated? I assume not.

-Gonzo

A lift ? I'm so jealous.....I can't even put a door on my garage, not enough room to swing the car in because of the community drive....Well, what do you want for a home that's valued at over $800,000.....A yard would be nice as well....

Welcome to life in Brooklyn NY.....

ENJOY THE Z.....👍

Gonzo_65_L76 09-06-2018 01:36 PM

I finally got some quality time in the garage. I first did a ~10 minute wash to get the main layers of dust off the car in order to see what I bought. The paint is in much better shape than I thought it would be. There's the expected amount of road rash that comes from ~50k of highway miles. One bummer is there's a decent spider on the hood where it looks like someone tried to shut the hood with something resting on top of the engine. Overall, I'm happy with the paint condition. A good polishing should really get it to pop.

https://cimg2.ibsrv.net/gimg/www.cor...bc0dd733c6.jpg

Up on the rack, the underside looked about the same - ~50k miles of grime. It appears from the grime patterns that at one time (maybe still) there was a leak in the oil pan gasket. The tranny, as you can see is black. The good news is that nothing is bent. It appears the car has never been wrecked, which is the story I got from the past owner years ago.

https://cimg1.ibsrv.net/gimg/www.cor...27133fac68.jpg
The good news is that I've been slowly inching away at the cleaning up the underside. I expect that will be nice and shiny by the end of the week.

And then there's the engine bay. Oy. 3 good size rat nests... 2 in easy to reach places with the shop-vac... the other... not so much.

Taking the plenum off was relatively easy. I am blocking the TB coolant system to cut this from a ~25 min job to a ~10 min job the next time I do this. I know its not ideal, but for now, I'm drilling, tapping, and plugging the plenum side of the TB coolant channel as I'm not pulling the heads off at this time, and don't feel comfortable drilling the head with it still on the block... even with a good shop-vac. Drilling the plenum will get me the same result except that the next time I pull the plenum, I might spill a little coolant if I don't first drain a couple drops out of the system.

Surprisingly, the vacuum lines are all in very good shape. That said, I removed the secondary vacuum system while I was in there. Because I'm not yet pulling the heads, I simply removed the secondary vacuum canisters, and safety wired the secondary runners in the open position. Again, things looked pretty dang clean... but then I saw a little tuft of hair. %$#&. Double-%$#&. I pulled the MAP. I then disconnected all the wires and pulled the DIS and found the main nest located in the center of the engine, under the starter. More shop-vac.

https://cimg5.ibsrv.net/gimg/www.cor...1b80cd2a60.jpg
https://cimg4.ibsrv.net/gimg/www.cor...3b1ef7e645.jpg

At this point, I'm spending all my time cleaning trying to get the barn smell out of this car while I wait on my gasket order from Jerry's. Interestingly enough, I've learned that soap and water with a toothbrush actually works better at removing baked on rat urine than Gunk solvent. In fact, Gunk does nothing to remove rat urine. Neither did brake cleaner or carb cleaner. Luckily, my garage has good ventilation.

I'll send more pics sometime this weekend, but my best guess for getting this back on the road is another 2-5 days (assuming I get my new gaskets in the mail in that time). Once you get past the smell (which is starting to lessen), the work is quite enjoyable.

Fun fun fun!

-Gonzo

ccmano 09-06-2018 01:57 PM

Looking good. I suggest while your in there remove the injector housings and put new lower gaskets in. Several, including me, have had failures of the lower IH gaskets causing oil the be sucked in from the breather galley. It seems to stem from the many heat cycles over the years, then the car sits a long time, then we bring it back to life driving it harder than ever. The gaskets I took out were like rocks. Keep up the good work!
H
:cheers:

mhobtr 09-06-2018 02:43 PM

Your experience is shaping up to be very close to mine. I bought a '91 that had not been on the road in about seven years. Tires were flat, ran awful and oil leaks like crazy.

First went with new tires, plugs, filters and then the fun began.

Turned out the main oil leak culprits were the studs in the engine block for the exhaust manifolds. This is a well documented problem and the fix requires a lot of contortion if you are not removing the manifolds, but it is doable and the fix eliminates the main leaks. I pulled the air injection system off the manifolds before I started and it made things a lot easier. I replaced the oil pan gasket while at it. If I had known then what I know now, I would have snatched those manifolds and installed headers then.

Injectors were original so they were replaced with FIC's from Jerry's along with new Vitol O rings. Secondary throttle plates were tied open and it's vacuum system eliminated.

New Haibeck chip went in somewhere around this time.

Still ran poorly and had awful hesitation when trying to accelerate. Took a long time to find but someone had installed a non-adjustable throttle position sensor. Replaced that and the hesitation was gone. Still ran poorly but a check of the coils revealed a bad one so new MSD's were installed. Now it was running better.

Then started running out of gas with a full tank. New fuel pump assembly helped but turned out that the new one had a faulty pump. Replaced it and installed metal hose clamps and that problem gone.

NOW it runs like it's supposed to and I have developed a real appreciation for it.

Also along the way, I installed the starter relay to eliminate "no start" issues; repaired the tach so it reads close to actual RPM: and installed a new low pressure switch to get the A/C going again after a freon charge. New weatherstripping all around was more fun that a man should be allowed but it looks great.

Soon it's going on the lift to receive headers, Corsa exhaust, stainless oil cooler lines and a short throw shifter.

Radio doesn't work but LT5 music is all I need to be happy. Maybe in a year or two I will drop in a new stereo.

Seems like the fun never stops. My wife may complain but hey, it keeps me out of bars.


All times are GMT -4. The time now is 06:35 PM.


© 2019 MH Sub I, LLC dba Internet Brands