Really need some help

B

bwdt

engineer
Joined
Oct 19, 2009
Messages
455
I'm trying to get this truck performing right and can't seem to figure out why I can't make boost. The truck has everything in the sig. I can only make 22lbs of boost with the edge turned off, and 28 lbs with the edge turned on. Truck smokes like a pig until I get to about 2400 rpms. constant smoke at accelerating light throttle. 2 lbs of boost when cruising down the highway at 65, at 1700 rpms. Higher then norm egts. Drive pressure are almost 2 to 1 and will max out at over 55 lbs. Innercooler removed and checked for leaks and plugging. turbo is a 63-74 -18 with a blade in the exhaust that will shrink it down to 9cms. drive pressure seems to stay the same with the blade open or closed. I will be rechecking the open pressure today on the newer exhaust housing I installed yesterday The cam in this truck is a Hamilton 188-208. New engine, new injection pump, runs really smooth, and great power. Just low boost, and high drive pressure. I'm thinking that there must be something wrong with the cold side of the turbo. No visible damage to turbo, boost rises very slowly, not like my old 62-65/12 which would make 45 lbs. no problem with smaller injectors.

Tests done are: leak test on intake to 70 lbs, disconnected exhaust and ran to check for clogged exhaust, no boost leaks, no plugged exhaust, two different sets of injectors 75 hp and 125 hp same issues, two different exhaust housings, turbo sent back to blaylock to get checked out and they said nothing is wrong.

I also get a vibration below 1400 rpms, it feels like an exhaust vibration in the down pipe, similar to what I have heard on larger diesels that are lugged.

everyone is stumped.

Any help would be greatly appreciated.
 
I don't know if you have already checked but I would test your boost gauge, but that doesn't explain the smoke I have purchased a turbo in the past that that was new and surged like crazy super laggy ended up being a bad unit do you have another turbo you can throw on even a stocker and see if it helps other than that looks like your on the right path.
 
The gauges have been tested. unfortunately I don't have another turbo, I sold the one I had along with the manifold when I bought this one. This unit uses a t4manifold and finding a t4 turbo to test is not easy. I'm waiting for a company to call me back that says that they might be willing to bench test this unit. If they can't I'll be selling it along with the T4 manifold and writing a scathing report of my experiences with the turbo. I hate to sell it, so I will probably be taking a 1000 dollar loss when I do so. I have grown tired of all the bs I get from the manufacturer telling me that its the truck or its me but it cant be the turbo. I'm convinced that the problem is on the cold side of the turbo, but I don't have a way to test to confirm. this turbo is suppose to run 1 to 1 and it has never gotten close to that, best has been just under 2 to 1.

Anybody need a bad turbo and a T4 manifold.:-(, I'll be selling the injectors as well.
 
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Check all the gaskets, make sure it's not loosing boost somewhere you wouldn't expect. The gasket on my intake shelf was shot & gave me a lot of the same issues.
 
You missed the part about leak testing it to 70 lbs, no leaks.
 
Just out of curiosity did you replace just the turbo or everything at once injectors and injection pump? It sounds like a boost leak or turbo to me but I have never drivin one where the inj pump is not keyed correctly. Out of curiosity who makes the turbo?
 
Sounds like a bad turbo to me.

A buddy of mine was having a similar issue, replaced the turbo with a new 62mm and was on his way.

Hope you can get this figured out.
 
I think your turbo has issues. I had the same cam in an '02 with a 62/65/14 and it would hit 40psi in a second.
 
Here's an update.

Put a new turbo on the truck it's a 64-71/12 from d-tech. less smoke but low boost. It' only makes 28 lbs of boost at wide open at 2800 rpms. This thing should be somewhere in the forties.

I'm stumped. I'm going to recheck for boost leaks for the fifth time, I don't think I'll find any, I'm also going to check drive pressure again.

Do you think it's possible that the cam could be defective? or indexed incorrectly?
Could an engine run great, and still have a 25% loss in boost pressure? I don't know the answer to these questions? I'm getting tired,

Pulled inner cooler, checked for leaks, pulled front cover to check timing, changed turbo three times, changed injectors three times, changed exhaust manifold three times.

What should I check for next?

Is there a way to check the cam without pulling the front cover?
 
I'd call Zach Hamilton and ask him the cam questions. No one will have answers as good and as fast IMO.

I'm assuming you checked the lower boost boot down on the bottom, passenger side where the inner fender panel likes to rub a hole?
 
I know this sounds kinda of out there but it's worth a shot. Is there any way a rag could have gotten into the turbo side of the intercooler. I had put a rag in my intercooler pipe to keep crap from falling into the pipe while swapping a turbo and subsequently forgot about it and almost drove my truck before I remembered the rag. I started it and it ended up blocking part of the intercooler and was a real pain to get out. Unless someone knew it was there it would be almost impossible to find. Had to use a coat hanger to fish around in there and snag it.

It would also explain all of your symptoms and why a boost leak check would come up with nothing. Just a shot in the dark but anything is worth consideration when you get to the point your at.

Good luck!
 
Here's the update:

I put a 64-71/12 from d-tech on the truck, probably should have been a 63-68/14 but got talked into the latter.

I am now making 1 to 1 on boost and drive pressure. spools at around 1700 (wish it was around 1500) I will be getting my EGT numbers today.
As to the Boost numbers being lower than what I expected, Zach said that they are on the low side but they are still in the range of normal.

I talked to Weston (great guy, extremely helpful) what I learned from him helped out tremendously.

I raised the injectors by forty thousands and it eliminated about 80 percent of my smoke issues, it changed the sound of the truck and it runs awesome, but still with a little to much haze. fuel economy came up as well. So now I'm going to have to have a custom set of injectors made with a wider spray angle and a slightly higher pop pressure to clean things up.

Max boost is only 32-33 lbs and max drive pressure is around 35-36 lbs. cruising down the highway is around 2-3 lbs. I believe that these numbers are about all I will get with the Hamilton cam.

The truck is a lot snappier and flat moves. Definitely needs traction bars. LOL.

It's a hoot to drive.
 
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