I put an hx40 with an 18cm exhaust housing on my 1st gen. The most boost I can get is 15lbs. I've plugged the wast gate and nothing changes. The pump is turn way up. I have lots of black smoke which I'm assuming is from the lack of boost. I am confused. I thought I could easily reach 35lbs of boost no problem.
Also my egts get high quick. But I think that may be related to not enough boost alowing the gasses to escape quick enough. I feel really disapointed that I put this turbo on. Is there any help out there to make this thing build boost.
Thanks

 

Check for boost leaks. And then if that don't fix it check again.

 

where should I start. The inner cooler boots where fine before. There doesn't seem to be any leaks that I can find.

 

Hmmm.....I had the same problem on my 95...I couldn't get any boost...but just smoke and high EGT..

What I found....The fellow who had it before...Overheated the HX40 so bad...that the bushings where shot...I guess it was locking up when I tried it on my truck...The person that bought the turbo...told me the bushings where shot because of being over heated...

 

did the shaft turn freely by hand when it was on your turck. Did you ever put new bushing in it. Mine has zero play in it. and doesn't bind on anything. I'm really stumped.

 

What else do you have done to your truck? Don't see anything in your sig.

 

This. Check every boot, clamp and tube in the system not leaving out the intercooler. Pressure test it. Even pin hole leaks don't help.

Also, check for leaks on the exhaust side. Head to manifold and manifold to turbo gaskets that are bad or blown with hurt spool as well. Exhaust leaks should be easy to find.

 

Yes...it did turn freely.....But I did catch it once...Where the shaft was stuck..That should of indicated to me...The turbo had a problem...The fellow who bought the turbo...took it a part...Sure enough...the bushings where bad from over heating..

Not saying your turbo is bad...You could have a boost leak..But if no boost leaks...Could be a turbo issue...

 

Well. I pressure test the system. I put plumbers cap on each end and presurized to 25 psi. And held it there for 10 min. No loss in pressure.
maybe hx40 turbos don't work on 1st gens. My intention is to build a more effient truck for towing. The only thing I do with this truck is pull my 18,000 pound fifth wheel. I'm afraid I'll cook it if I hook on to her. Empty I hit about 1270 deg. The only things I've done to the truck are rotate fuel cone, turn the star wheel down, turn the fuel screw in. I Put an elbow off the cold air intake a put a k&n air filter on and 4" down pipe off the back of turbo. I really need to get this working. Thanks everyone for your I put thus far.

 

Did you try wiring the wastegate closed?

 

yes.