Ok.

ive got a dilemma. I have a very nice heavily mod'd 93 corvette.

Recently, I got an 8k cluster from (what I am told ) a 93 zr1. I needed the one with the orange lettering to match the rest of my dash font.


First issue:

max printed oil temp on my car (w/ stock 6k cluster) reads 320F, max printed oil temp on this zr-1 8k instrument cluster reads 280F. Is this ok?

**update** no, its not, my oil temp is reading 20F low on the new 8k cluster vs. what it really is from measurement w/ digital thermometer probe.

**Also coolant temp digital readout reads 142F*** It is actually at 52F from measurement w/ thermometer probe.

Main issue:

The cluster I got looks like it has sun-faded orange needle pointers vs. my mint condition cluster in my car.

This wouldnt be a big issue, but... Recently, I had redline good stitch up new shifter boot and console lid cover with orange stitching to match the font of my dashboard. It looks awesome (see picture).

Is there any way to remove needle pointers from my 6k cluster and put them onto the 8k cluster? Without damaging it?

 

It would probably be easier to paint the needles.

 

You'd be smart to test(install) the 8K cluster before you take your other one apart to rob it for parts.

Pretty easy to get'em off.


Getting them "lined" back up to read "correctly" is a different story. I've read an older thread here on the CF which describes sucessful needle removal reinstallation though - do a "search"

 

OK, that video sure made it look easy.

In between my initial post and now, I plugged the new instrument cluster in and verified its function.

I was kind of amazed how easy it was to plug this thing in btw.

Now. I have another problem...

Oil temp digital readout (w/ new 8k cluster) reads: 33F

Coolant temp digital readout (w/ new 8k cluster) reads: 142F

I stuck a digital thermometer probe down both my oil dipstick tube, and into the coolant radiator reservoir and these are both at 52F....

Also...the coolant analog temp gauge (on the new 8k cluster) does not indicate the same temp that the digital gauge reads. Its just pegged low. Who knows, maybe its reading correctly.

If anyone knows what I need to do to sync those and then get the digital gauges to read correctly, please let me know.

 

142* is a default reading, sounds like the CTS is not communicating with the cluster.

 

I'd say first of all let's see what you actually have for an 8K cluster. What is the 8digit number on the label on the "back-side"! It's going to likely be one of these:
16133461/3451 - '90MY
16142481/2471 - '91MY
16188841/8861 - '92MY & '93MY

Your '93 6K is probably a 16158831

Comparing those #'s can tell you if the LCD is a match or if it needs swapped. I don't recall all of the combinations that are possible. If you knew all of that then you could see if just swapping pointers is going to accomplish your task.

I believe I'd have a cluster shop do the needle swap and a calibration on all of the gauges. Now if it's a '93MY maybe all you need to do is swap the tach package and the board on the back that has the tach chip and calibration resistors. In that case you could just get the tach pointer swapped.

I hope that all made sense but I believe that if it's a '92 or '93 you get the pointer swapped on the tach package by a shop and you're all set.

 

New 8k cluster...16158841, says 'LAC' LT5...Delco Electronics Corporation

The old 6k cluster says 16158831 (as you correctly said), 'LAB' LT1...Delco Electronics Corporation

 

That stitching does look great!

 

I'd say you're pretty good to go. At least the tell-tales and the LCD are a match. Is the LCD bright on the 8K?

I have a '93 cluster here and I took it apart to see if the pointers removed easily. I used a large serving fork and a couple were very easy and a couple were tougher. They all did come off though. There's a tab on them to limit the sweep!

See what you think of this idea, experiment with your 6K tach and remove the pointer. Install the cluster in the car and with the "key-on" the tach should be parked at 0 - carefully install the pointer to 0 and then try it! I don't recall what the tach does if you just use the accessory position on the ignition. The cluster has stops on it and it can only sweep so far. Remove it and attempt it again and see how successful you are in placement. Practice a couple times.

If you do well move on to the analog gauges and see if you can duplicate their placement - key on, car "cold". If you wanted you maybe could calibrate the temp pointers if they required it after the fact and you found you were proficient at it. The volt gauge maybe calibrate yourself after confirming it.

I think I'd go for it but I'd experiment with the 6K unit.

If you're not up to that I think I'd just color (paint) all of the needles on the 8K to match with a florescent from a hobby store. Only one surface of the needle gets colored, they're plastic and meant to be transparent.

If you want a '93 cluster to "dick' with this '93 is completely disassembled and I could put it in a box for you!

 

I haven't taken anything apart yet, but I searched corvetteforum and found out that the 8k tach part (including the graphic) can be separated from the rest of the cluster.

Since I'm havng trouble w/ the other gauges (oil temp and coolannt temp) reading correctly, then why don't I Just transplant the 8k tach into my 6k stock instrument cluster.

That way I only have 1 needle to change out (the tach needle) vs. Having to swap out all the needles on the 8k cluster (for the brighter orange needles).

 

This cluster here is completely disassembled and yes the tach is a removable component.

I'd probably install the 8K cluster as it is and confirm everything after some "run-time"! Drive it!! If you want to transplant the 8K tach you'll need to swap the board also because the tach calibration etc is on it. Do you have a scanner that you can use to confirm the actual temps etc?

Something that's not been mentioned but might require some thought, the tachs in the earlier analog packages were notoriuosly erratic and failed frequently. I believe it was corrected earlier than '93. You need to verify the tach operation.

You've got the R&R down now I'm sure, the next time it should be a piece of cake!!!

Good luck!!!

BTW - I didn't check out the video until after I had removed the needles. I didn't have as difficult a time as was displayed in the video!

 

Sticking a probe into the dipstick tube and the reservoir will not give you the same reading as the temperature sending units in the block. The oil in the sump will always be much cooler than the pressurized oil in the block lubricating and cooling metal components within the motor. The coolant reservoir also isn't the same temperature as the coolant in the block or even in the radiator.

 

I understand your point, but the readings were obviously wrong.

No way could coolant be 142 F when its been a week since I started the car.

Also, oil temp reading 33F in an unheated garage that was 62 F and the evening low didnt drop below 40F.

 

OK! I transplanted the 8k tach into my old cluster. I want to do it this way because:
1. I want my old analog temp, coolant, etc. gauges to read correctly
2. I wont have to replace out all the other gauges needles since they arent faded out like they are on the LT5 cluster.




I had no trouble prying off the the faded needle using a plastic disposable fork. The needles have a small counterbalance weight inside and rely upon gravity to 'fall' to the correct resting position. I used a .5mm pencil to create a small dot where the needle should 'fall' to. After a couple tries I got the new needle to 'fall' right to the dot where the old faded needle fell.

I will still need to check for accuracy using a scanner, but thats no big deal.

Knowing what little I know about electronics, I suspect I will have to swap out the resistors in the tach circuit also since they are different. Ill have to put the resistors from the lt5 board into the lt1 board. I suspect these resistors are the only differences in the tach circuit on the circuit board. Please correct me if Im wrong. These resistors are circled in the lower left of the picture. Also, I dont know if you can see, but 'TACH' is printed on the board near the resistors so its clear that these resistors are related to the tach function.



There were also 2 IC's that had similar, but slightly different, numbers on them. One read:

LT1 cluster: 014 55453 P9246
LT5 cluster: 014 55453 P9215

The other IC read:

Lt1 cluster: 9907A CS9250J
LT5 cluster: 9907A CS9149J

Unless anyone else here knows differently, I suspect these IC's control the other non-tach gauges (oil temp, coolant temp, etc.) or the fuel economy / trip odo functions- which I want as my default LT1 gauges.

The LCD crystals, surprisingly, have the exact same P/N's and should be 100% interchangeable and not need any modification.. The flash of the camera washed out the numbers to the right of the p/n for the crystal on the left, but they are the exact same.



Everything else on the boards were identical.

Sooo....

Im going to swap out resistors from the LT5 board into my LT1 board. With any luck, this thing will read accurately.

 

You're right about the temperatures. Obviously, I sometimes type without reading. Looks like a major job. Good luck!

 

I'd be inclined to just put it together with the LT5 board and check it! Confirm with a scanner the calibration of the gauges and tach - maybe be able to move on!!

 

Ok.. I figured it out...

My coolant temp at 142f was because I had the sensor, at the waterpump,unplugged.

The oil temp read 42f today in a garage tht was 56f so I guess that's more reasonable.

The tach....remember I replaced the pointer. When key turns on (engine off), it goes to 800 rpm. So I need to point the needle down more.

I'm using the zr1 board and crystal, with my old analog gauge (right side) cluster plugged into the right side.

I've got my motor down for a cam change so it will be a while before I can test the tach out and make sure it works properly.

 

Try setting the pointer to 0 RPM with "key-on"! I mentioned that earlier!!

 

Hey guys, thanks for this informative thread. I'm turning my 92 LT1 into a LT4 and this is helpful, as I want to swap my tach to an LT4 8 grand tach (if I can find one).