Lack of Boost?

[Dave7.3]

Well, I'm not quite sure what is going on. I didn't have a chance to bump up the fuel on my truck since the turbo install until this evening. Two flats yielded light black smoke at WOT so I think that is about where it should be. I haven't highway tested it yet but EGTs seem to be in the 800-1000*F range. Room for a little more, but don't want to risk it as this is testing while unloaded.

Now, I have a brand new autometer sport comp II series boost gauge. My original installation kinked the boost line all to hell, so I replaced the line and used a small coupling to rejoin the two lines. I can no longer hear a hissing noise so I think it is air tight now.

Problem, no pressure registering on the gauge. Tested the gauge, seems to be fine. Shows pressure with an air hose so it can't be that. I replaced the small compression fittings (bent one of them badly) so I don't think it is leaking at either point. No kinks anywhere else.

I know the turbo is spooling as it whistles like a damned jet taking off. But what is the deal? I'm at a loss at this point. Tightened up the intake hat all around and no fix there. Can't even detect a hissing sound of any kind. Ideas?

-Dave

 

[dyoung14]

Replace the line from the engine to the turbo

 

[Dave7.3]

Replace the line from the engine to the turbo

I was afraid of that...wish I hadn't coated the spot where it passes through the firewall with a dab of silicone! Think that coupling isn't holding pressure?

 

[dyoung14]

I was afraid of that...wish I hadn't coated the spot where it passes through the firewall with a dab of silicone! Think that coupling isn't holding pressure?

Well its hard to say, the only way to find out is change the hose, i wouldnt trust a coupling on a boost line but thats me

 

[Al_E]

Probbably over tightend it and pinched it off, Darn 1/8" line.

 

[Dave7.3]

Probbably over tightend it and pinched it off, Darn 1/8" line.

I know what you mean! I ruined two sets of couplings on that 1/8" line! Might be the easiest fix to go through and replace that line like dyoung mentioned. Thanks!

 

[dyoung14]

replace it and let us know

 

[icanfixall]

Is the boost line plastic or copper. This small of a line sometimes gets closed off where you cut it. My oil pressure gauge was not working years ago because the line was copper and I had used a tubing cutter to trim it. The line almost completely closed up. The gauge worked real lazy and slow to pressure up and down... Sure was crazy till I found out what was wrong. Finally changed to an electric oil pressure gauge. Thats gone bad twice now and I'm working on my third gauge from isspro... Not a good thing either....

 

[dyoung14]

I liked my mechanical oil pressure and water temp gauge till the oil line blew and filled the cab with oil, and the water temp gauge just up and stopped working how does a mechanical water temp gauge stop working

 

[93f250idi]

I liked my mechanical oil pressure and water temp gauge till the oil line blew and filled the cab with oil, and the water temp gauge just up and stopped working how does a mechanical water temp gauge stop working

idk unless the end got calcium build up or whatever it is haha.

 

[Abull78]

where did you tap to get the boost pressure from?

 

[rhkcommander]

been having the same problem, compression fittings weren't compressing and popping the hose off for me. Now I suspect a kink somewhere cause it still dont work

 

[Alex S]

how does a mechanical water temp gauge stop working

mine went on strike for a day

 

[dyoung14]

mine went on strike for a day

mine been on strike for about a month i just hooked my factory ones back up along with my mechanical ones

 

[Dave7.3]

where did you tap to get the boost pressure from?

I tapped right into the intake hat where Hypermax already put in a plug for it.