Installed my $18 boost gauge last night, black smoke explained! [Archive] - Diesel Place : Chevrolet and GMC Diesel Truck Forums

: Installed my $18 boost gauge last night, black smoke explained!


Veggieburninburban
04-16-2010, 09:33 AM
Ive got a 93 3500 4x4 with manual transmission and 599-block 6.5TD, mechanically injected and mechanically boost-boost controlled. The IP has been turned up like 3/16 turn. I run it on 100% biodiesel of my own make in the summer, and 100% diesel in the winter. I run mixes during the spring and fall.

I have noticed a little bit of a drop in "giddyup" over the last year, that and an increase in the amount of black smoke upon acceleration. I replaced the air filter (OEM, flat panel type) a couple of months ago with no noticable difference. I pulled the filter side hose off of the turbo and checked it to make sure it didn't have too much play, that the vanes weren't contacting the housing and that it spun freely. There was a tiny bit of axial play, no run out to speak of, and it did indeed spin freely. Next in the line of suspects was the golden pop can on the bottom of the turbo. I suspect that the spring has gotten weak. The linkage moves with no hangups or rough spots.

So last night, I pulled the upper intake manifold, drilled and tapped in the spot where they put the Air Intake Temp sensor on the later models for a push-lock fitting, I ran 1/4" black poly hose into the cab, and put a $10 -30-30 PSI gauge on the other end. I didn't get a chance to test it out last night, because I put the kids in bed, so I couldn't leave the property. (That and I got busy building an Egyptian AK!)

Anyway, on my way to work this morning, I noticed that I was getting a consistant 5 PSI upon hard acceleration, and 2 PSI while cruising. I understand that this year of 6.5 was supposed to have something like 7 or 8 PSI on WOT and 3 or 4 while cruising. So I surmise that the spring in my "golden pop can" has gotten wimpy. I'm planning on cutting off the end of the can tonight and tightening up the spring a bit.

This is a daily driver, not a real workhorse. I do tow a flatbed trailer loaded with veggy oil barrels from time to time, but when I do, I go real easy on it. My goal is to get back the giddyup without blowing up.

My question for you fine fellows (and gals) is this: How many PSI should I limit the WOT boost to? I've heard some say that 10 is the safe max.

Veggieburninburban
04-16-2010, 09:39 AM
Oh yeah, my other question is: Where can I find that thread with pictures detailing the wastegate controller (golden pop can) mod?

Bison
04-16-2010, 10:44 AM
its called a Turbo master

Veggieburninburban
04-16-2010, 11:30 AM
I found it. Here it is: http://www.dieselplace.com/forum/showthread.php?t=347127

I'm going to do this tonight.

Veggieburninburban
04-19-2010, 10:27 AM
OK! So over the weekend, I did the Turbo Master mod. Whooee! What a difference! Now I only get smoke when I really mash the pedal (or lag the engine, in too high a gear). I've got the power back. Now My boost stays at 3.5-4 psi while cruising, and maxes out at 9 psi when I'm really riding it hard.

This is a really worthwhile mod! Thanks dieselplace!

farmboy56
04-19-2010, 12:04 PM
You could play around with it like I did now that you have a boost gauge. Adjust it so when you are at 2,500rpm it goes up to 14psi after mashing on the throttle but settles at around 12-13psi and hold on!!! I turned up my injection pump til the screw stopped, installed 40hp marine injectors, and installed my turbomaster all in one weekend and was SHOCKED with the increase in power. Been running my current setup for about 28,000 miles now.

Veggieburninburban
04-20-2010, 08:22 AM
I'm afraid to go too radical. I'd like this engine to last for a few more years, so I think I'm going to leave it where I got it for now!