Discussion in '6.9L IH & 7.3L IDI Diesels' started by homelessduck, Apr 16, 2020.
Some goodies showed up today! Thanks again Russ @typ4 !
It was a beautiful day today so I finally got some more work done. The engine is just about buttoned up. I dropped the new rad in and realized it has the bottom ports plugged. Originally there was a T in the coolant lines that ran to the bottom passenger side of the rad. I'm sure I can just eliminate that T..? Every IDI I've had with that hose running to the rad the hose was 100% blocked by gunk. What is the purpose of this hose?
It was intended to heat the trans cooler in the radiator when the engine is cold. Not sure how effective it is. Mine was cut off when I got my truck so I have been running without it. Seems fine.
Ok awesome. That's what I was thinking. I will eliminate it then.
I deleted mine but I don’t worry about heating up my ZF.
Well a lot has happened since my last post. The truck is back together and running. It fires up instantly and has zero smoke when cold. Once it gets warmed up and under a load it POURS grey/white smoke and idles a little rough. At the same time it starts leaking out of a return cap. It doesn't leak when cold , only when it warms up and it doesn't affect starting at all. I went to check the timing but the damn timing tab tube that the probe goes in is loose and flops around. I will probably try to weld it instead of pulling the whole front cover and replacing it. I'm going to replace the return orings on the leaker tomorrow but as far as I am aware return line leaks shouldn't affect the engine after it's running.. Only start up. It isn't losing coolant or oil. It passed a cooling system pressure test.. More trouble shooting tomorrow.
@homelessduck is the leaking cap seated good like it is down all the way?
more importantly, does your truck high idle/cold start timing advance work when the truck is cold. when it is cold the timing is advanced by 10 degrees it almost sounds like the timing is retarded by 10 degrees, which would explain the smoke when warmed up
Ya it's seated , I probably twisted an o-ring while rolling them on. Yep it works just fine . But the leak and smoking doesn't happen when the truck kicks down , it only happens when it gets some heat in it under a load. I was thinking it might be really retarded which is why I tried to time it. The engine ran good before I put it in my truck and after getting it installed I set the pump at the same spot so I wouldn't think it would be significantly off.. but I'll tack that timing tube tomorrow and check the timing.
@homelessduck is your IP and injectors new?
Fresh injectors , rebuilt pump .
Getting closer .. Hopefully lol. I replaced the leaking return o-rings... But I apparently bumped the one next to it because it started leaking lol. So I replaced those too , she's all dry now . I decided to just use a cheap gasser timing light with my meter instead of fixing the probe hole. Timing is at 9.5* . Smoke is completely gone! It still stumbles here and there.. And after driving it a mile or two it starts loping in gear. Switch to neutral or park it idles normal , back to drive / reverse and it lopes bad. It is definitely down on power. I'm going to throw a bottle of diesel treatment in the tank , since the truck did sit for like 10 years I'm sure there is junk in the tank. And toss another fuel filter on it. I ran the truck down passed 1/4 tank so I don't think the shower head broke off and clogged the fsv... But that will probably be what I check next .
That is one nice rig you got there!
If you want to really clean up the fuel system, run 40% kerosene to 60% diesel and you will be amazed how that stuff cleans everything from the tank to the IP and everything in between.
I pulled the front tank sender the other day. The shower head was still attached..barely. It broke off as I pulled it out. It broke down in to a black goo. I replaced it with some hose and ran new fuel lines from the front tank , bypassing the fsv. It appears to have fixed the air intrusion issue. Here is what the fuel that came out looks like.. The picture almost makes it look like off-road dyed fuel , but it's more of a yellow in person.
I finally got the alignment done and she's back on the road! It still idles rough , I need to figure that out.. But other than that all seems well!
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