So I've been checking for boost leaks, and I can hear air hissing out, apparently from the intercooler (pipes and boots are OK). Of course I can't see the leak with the radiator in the way. Before I go tearing everything apart, I was just wondering, are intercoolers repairable, or do they just have to be replaced?

 

I'm gonna say replace. Maybe a radiator shop could patch it up but the cost of that will take you to spitting difference to a new unit.

I think if you remove the rubber tool shelf you can get a look down there.

Got a boost leak detector?

 

If it were me I would replace it. The 6.0 IC is an option as well a the 7.3 IC. The prices range from ~$300 - $1000 for new and varies for used.

 

Some times the tubes to and from the intercooler get holes in them also. They rub on things and cause holes.

 

So they are completely interchangeable?

 

The 6.0 IC requires a slightly larger boot from the IC pipes, and the IC itself is a tighter fit as I understand it. A lot of people have installed the 6.0 IC into their 7.3. It is not uncommon, but it is not a very common modification either because rarely do they go bad and the OEM 7.3 IC works pretty well.

 

If it were me, I'd pop the hoses cap one and put a vac gauge on the other before I wrenched. If it holds>>>>>>>>>>>>>>>>wasted time and money. Could be anything in line compromised. Why not start the ruler?

Denny

 

BTW. you can move the setup to the other end of the hose and check to see if it holds. Simple testing and minimal wrenching. I think your better off going this way to eliminate parts.

If you don't have a vac pump I'll loan you my own. Like 30 bucks to buy and on a 7.3 u want one. 2nd drawer!

When you pop your boots take a fine grit paper and clean your pipes. Be observant of cracks, corrosion or anomalies. After their spotless, Take 40 grit to a 1/2 inch section where the hoses terminate. Rough it up

Put a clamp there, and a clamp upstream where you polished it. Test it. If it holds, hoses and IC are good. If that pulse is dead you need to look aft.

Denny

 

Not to be your girlfriend on the forum, but it just struck me that you say you can hear a whisper, but you didn't say anything about performance loss. Your just chasing a noise?
Need a good story.

Night

 

No, not just chasing a noise. Power and MPG seems a bit ho-hum when pulling a trailer. Turbo sometimes seems kind of laggy. Have noticed a high-pitched whistling noise from time to time at high RPM under heavy load; it will start all of a sudden and usually not stop till I go to a higher gear.

Here's what I've done so far:

1. Removed air filter and attached home-made boost leak tester to orange tube. Disconnected and capped left blue hose (cold side). Could hear air hissing out near the cold side.

2. Replaced 4 blue hoses and cleaned up the connections real good. Hissing unchanged. Removed cold side pipe and tested it with both ends capped. No leak.

3. Thought it was an intercooler leak. Disconnected both blue hoses shown in picture, capped, and applied pressure through both pipes and the intercooler. No leak!

4. Finally found the source of the hissing noise. It's coming from the dipstick tube. But this doesn't make sense to me. The cold side pipe was disconnected at the engine and capped. Air is getting into the crankcase when I pump air in through the turbo compressor, but not when I disconnect the blue hose on the right and pump air directly into the hot side tube. So air is somehow getting into the crankcase via the turbo? I felt the turbo shaft end play by hand and it seemed minimal/normal.

 

It't going threw the PVC vent at that point and into the crank case. But at least you know the intercooler system is healthy. Have you pulled off the oil cap and turn it up side down to see if it stays in place? Also any blow bye?

 

You have to disconnect and cap the CCV when doing a boost leak test or it will pressurize the crankcase and you will hear it leaking out of the dipstick tube or oil fill cap, there is also a possibility of it blowing out a seal.

 

Have you also checked the up pipes?

 

OK, thanks for the CCV info. There is no blowby, just a little light vapor that comes out the oil filler tube. I'll check the up pipes too. I should look for soot around the joints that would indicate an exhaust leak, right?

 

Yes, but if there factory one, update because they are leaking. Couldn't see any soot on mine but they fell apart when I changed them.