Newbie

[Mel Langford]

Does anyone know where I could get an air intake filter system for a 1990 Chevy. 6.5 turbo in a 3500 chassis?

[Dvldog8793]

Howdy and Welcome!
Are you looking for:
Something aftermarket...?
or
Something to use because you do not have an intake system?
or
Something to be an improvement over factory for your year?

[Mel Langford]

Thanks for reply.
Guess I should have started with a little more detail.
What I have is, a 11'-6'' camper on a one ton Chevy.
A little much for this engine, but, like they say,"run what you broung"
When I get in a pull, she starts making quite a bit of black smoke.
If I can keep the RPM up around 3K it's not to bad but that's not always possible.
I would like to replace the stock air cleaner with something that will get more air to the turbo and thought one of these after market units would help but I can't seem to find one that's made to fit this truck.

[Dvldog8793]

Howdy
IMHO...
The factory filter setup that uses the ROUND filter is actually not too bad. I think your truck has the flat panel filter which has a number of problems. So an easy upgrade would be to go to the local salvage yard and find a newer truck and use the factory setup for that.
The aftermarket window for our trucks is pretty closed. I don't know of anyone currently making an intake system for these trucks. You might find one on Ebay.
If it were my truck-
= round air filter system.
= open up the exhaust, either by just "cleaning up" the original system, or by installing a after market system. The exhaust on these trucks can be VERY restrictive from the factory. mainly the down pipe, crossover and soot trap(if it still has one)
Depending on how you do those two thing, it can be very cost effective "seat-of-the-pants" power increase.
There are lots of other options but then you start spending real money.
Another thing to really pay attention to is engine temps. Running that kind of load and RPMs I would think you might be getting into the danger zone for EGT and engine temps.
The engine cooling system on those early trucks was really undersized and inefficient.
Hope this helps.

[DmaxMaverick]

First of all, what do you really have? You either have a conversion, or the year or engine isn't right. The only GM LT Diesel option in 1990 was the 6.2L N/A (Natural-Aspiration = no turbo). If it has a turbo, it was added later. From your description of performance, it sounds like you have an original N/A 6.2L, and no turbo. If you are seeing a lot of black smoke at any time other than beginning acceleration, something is wrong and you are headed for a melt-down, turbo or not. I suggest at least pyrometer (EGT gage) before proceeding with any modifications. Without, it's just guesswork and you won't see the result of any subtle improvements or negatives.

Improving air intake flow can decrease black smoke, IF air flow is initially restricted. It is no cure in and of itself. If it clears up at higher RPM's, air flow is a much less likely suspect.

[Mel Langford]

Thank you for your time.
What you're telling me makes great sense.
Exhaust is already 3'' so I'm good as it's going to get there.
Yes I have concerns about the heat so I installed an electric fan and a "on demand" water mister in front of the radiator. If I see a problem with heat, I flip a switch and water is pumped from the camper to the front between the electric fan and the radiator. This fine mist of water will bring the heat down within a few minutes.
I think I'll work on fitting a round filter in there.

Thanks again,
Have a great day.

[DmaxMaverick]

While coolant temperature can be seen coming and going, exhaust gas temperature as it reflects in coolant temperature is inadequate. Excessive EGT, in real time, is a matter of a few seconds, not minutes. If you are making a lot of black smoke under heavy load, your coolant temp swings won't indicate the immediate condition of the exhaust gas.

Does it have a turbo, or no? If so, which one? GM 6.5TD, Banks, ATS, CTS? Is this a van, pickup, or Workhorse chassis? 3500 or 3500HD?

Pictures of the rig and engine compartment would be helpful.

[Mel Langford]

Yes Sir, it does have a turbo.
I will be back with the info. you requested.
I am checking on gauges for sure.

Than you, so much for your assistance.

[Robyn]

A boost gauge is in order as well.

With all this black smoke, whats the turbo doing ??

Another real possibility is that the injection pump has been turned WAAAAAAAAAY up.

If a boost gauge reveals good boost under load (8-14) psi and the coal is still rolling, then the pump has likely been turned up too far.

Under a hard pull after the turbo spools up, the exhaust should be barely visible if at all.

A touch of gray is all and normally not.
A short puff of black as the pedal is mashed is fine, but should clear just as soon as the boost comes up.

As Maverick mentioned, Exhaust gas temps are CRITICAL on these engines.

Post turbo temp (close to to turbo in the down pipe) should not exceed 900F

Right at the outlet of the left manifold in the cross over pipe the temp should not exceed 1000F

The best spot for a temp probe is the LH side of the cross over just below the 3 bolt flange in the vertical pipe section.

A WORD OF CAUTION

Some clown in the past (exhaust shops and others) have used a torch to blow a hole in the pipe so they could weld in a fitting for the temp probe

BAD JU JU

All the slag from that exercise goes out through the turbo at high speed and will trash the turbo instantly.

Get some gauges (boost and pyro) on board and lets see what you have going on.

A fitting for the boost gauge can be fitted by removing the air plenum from the intake and drilling and tapping a 1/8 pipe threaded hole to connect a small tube for the boost gauge.

Good luck

Missy

[Mel Langford]

Thanks to you all for the great advice.

I all most don't want to tell you this but I noticed that I started off this by telling you all that this was a 1990; It's a 1994. I've been working on a 1990 New Yorker for several weeks and I guess that number stuck in my mind.
Now I know why DmaxMaverick was questioning what I really had. SORRY.

I'm on my way to pick up gauges (pyro. and boost) and a kit to make a new air filter system.

I had a new injector pump installed about a year ago but have no idea on the setting. Will have that checked as well.

Thanks again; You guys are a great help.
I'll keep you posted.

[DmaxMaverick]

Well, that clears up a few things (except the smoke). We still need to know what chassis you have, and is it EFI or MFI. Does it have a throttle cable, or does it have an electronic accelerator pedal? Your problem will likely be very simple, but we need to know this. The 1994 model year was the first year for EFI, in MOST models. There were exceptions, and the chassis is the key. If this was a post-production upfit (classified as motorhome or "motor-coach"), it could be any of the above. If it's a simple pickup with a camper on it, then that is very different. Then there's the fog of modifications since original, which could be anything under the sun.....

[Mel Langford]

Back with comments and in need of advice.
I pretty much eliminated the black smoke with the installation of a round air filter assembly from B&S. This is a great unit, all enclosed and pulls air from the stock intake opening in the fender.
Installed a boost and Pryo. gauge. EGT will climb to around 900 when in a pull so need to keep an eye on that.

New problem; coming home the other day, power dropped drastically.
RPM went to +/- 2K and I could only get 19 MPH. After limping home, I shut it off and then started it back up and she ran fine. Is this the TPS?
Looked on line to see where this is located, etc. but having trouble finding anything on this for a 6.5 turbo diesel chevy.

Help!

[DmaxMaverick]

Start here:


......We still need to know what chassis you have, and is it EFI or MFI. Does it have a throttle cable, or does it have an electronic accelerator pedal? Your problem will likely be very simple, but we need to know this. The 1994 model year was the first year for EFI, in MOST models. There were exceptions, and the chassis is the key. If this was a post-production upfit (classified as motorhome or "motor-coach"), it could be any of the above. If it's a simple pickup with a camper on it, then that is very different. Then there's the fog of modifications since original, which could be anything under the sun.....

[DmaxMaverick]

BTW....
The power loss and speed limit was Limp Mode. You need to read the trouble codes to know why this happened. NOT likely the TPS, if it has one. Reply to the above post, and we can move forward.

[Mel Langford]

Back to my issues with my truck now that Christmas is over.

Clearing up some of your questions from last post;

It is MFI -
Has a 9 pin electronic TPS accelerator pedal. (tried a new one with no change)
Chassis is a standard one ton dully with a 11'-6'' Lance camper.

[Mel Langford]

:confused:
Back to my issues with my truck now that Christmas is over.

Clearing up some of your questions from last post;

It is MFI -
Has a 9 pin electronic TPS accelerator pedal. (tried a new one with no change)
Chassis is a standard one ton dully with a 11'-6'' Lance camper.

[More Power]

MFI - Mechanical Fuel Injection, usually a Stanadyne DB2 fuel injection pump for a 6.5TD.

EFI - Electronic Fuel Injection, a Stanadyne DS4 fuel injection pump.

In an EFI system, excessive black smoke usually means the electronically controlled turbocharger isn't generating the correct levels of boost pressure.