Compression Check

[hakcenter]

This post is more of an informative one. But the Harbor Freight cheapy special, part number 93644, does have a fitting that fits the Cummins 5.9 12v.

I had to grind the lower lip of the tool (bottom right one in the package) to get it to fit deeper for thread engagement. I also had to use just 2 wraps of teflon tape, each time moving the tool, no bigs.

Numbers
360 / 365 / 380 / 360 / 380 / 380

The first time around I really wasn't super checking, just wanted to see numbers over 340. So #3 #5 #6 were re-tests. Numbers look good enough to me that I don't have any real issues. Next up is the bore scope for $20 on amazon I'll update the thread to see how that goes.

[hakcenter]

Cylinders looked pretty dang good. I had used a metal bore scope the other night, so I imagine that's the shiney in #1 cylinder.

#1 looks like it has carbon outside the dish, so that's probably my bad injector.

But awesome tool for $20, here

[Rx7man]

I thought the compression would be a little higher than that all around.. I have a small diesel with about 320 PSI compression and it DOES NOT run worth a darn... You were thinking head gasket leak at one time right?  find any evidence of that?  Perhaps the low compression cylinders are to blame there though you'd think it would be bubbling out the rad something fierce if it was that bad.

[hakcenter]

Oh I imagine its a lot higher dang thing tries to start lol. But what do you expect out of teflon tape and 1/4" of thread engagement.

Getting over 300 just assures me its alive, and no cylinder is way out of another.

Some sources say 350psi is a new motor, 300 = rebuild, etc... I'm at basically 1000ft too, so I feel pretty good. Definitely not a toasty head gasket... I must have a hose that's drawing in air on shutdown.

From here...

New rebuild: 350psi
Good Used engine: 300psi
max allowable variance: 100psi

You should see the injectors though, hoooweee. 4 of them super wet, from only running 2 minutes to move my truck in the driveway. Chris @ DFI wants to look at em.

[Rx7man]

Head gasket leaks can be external as well though.. Mine pissed out from under the #3 cylinder but didn't get coolant into the cylinder.

[me78569]

I have always followed the rule of looking for numbers that are close to each other vs looking for a number to reach. 

Provided the engine runs ok, and all cylinders are within a few % of each other then I wouldn't worry.

[hakcenter]

Ya I'm not too worried about a head gasket or turbo seals at this point. I've been all through it. Check out these injectors.

Left to right, #1 to #6.
Truck still idled like a boss, nothing really out of the ordinary but strange white smoke after it warmed up, or sometimes while cold but always under light load. And once it started to have some white smoke, you could get it to do it idle + 1900rpm, then bring the rpms up and watch it just flow out.

Revving hard and riding its butt made the smoke go away, guessing cylinder temps for that but meh. Going to send the injectors back to Chris, and probably have Mr Farrell look at the 215 while I'm waiting on injectors anyhow.

[hakcenter]

So my white smoke is a pretty much constant now lol. I even bought new injectors from DAP 7x10's when they were on super sale.

Issue continues. My idle / injector rattle is completely gone which is nice I guess, it sounds overall better, but this white smoke is really starting to piss me off, it has to be a pump problem. I don't have nearly any blowby, truck runs like a f'ing beast, and this white smoke that is definitely raw fuel so somethings not right, maybe my pump is low pressure on the rail causing bad atomization ?

I never see any white when I lay into it, but low load ya cloud basically at this point. I've had it running without the valve covers to maybe see some kind of a compressionish issue and nothing. Cylinders 1, 3 and 4 are the only ones with any blow by coming out of the push rod area, the other cylinders nada. And by blow by, I mean, you can maybe possibly see with a flash light, there is a hint of it.

What was interesting was when I pulled my injectors 1,3 and 4 had fuel soaking on the tips. Certainly wasn't oil.

It's too bad I'm basically broke at the moment to try to send my pump out to Mr Farrell

[Rx7man]

weird... did you check valve lash since the HG job?

BTW about blowby, the valve covers don't correlate to pistons when checking it.. blowby from all cylinders goes into the crankcase, then just would come up whichever pushrod tubes it felt like

[hakcenter]

Ya I did valve lash like 4 days ago, it was really close, a couple slightly loose, but still no changes.

[Rx7man]

Weird!.. ever checked fuel pressure?  sounds strange since it happens at idle too and you'd think the truck wouldn't be making any power without fuel pressure...

[hakcenter]

Sent the 215 out to Seth basically 3 weeks ago!

Got some stats from him...
Pump info:
0402736913
181 dv's
stock dv holders
High LPC setting
100 plate
modified afc (35 psi boost for full rack travel)
4000 rpm kit
pinned at 15* btdc

max- 550cc
4- 470cc (set)
3- 380cc
2- 310cc
1- 260c

550 on 181's, that ain't too shabby.

Unfortunately Seth said that my b&p's looked awesome in the pump, but the GSK I had was basically garbage and causing all my low bottom end uneasyness (is we shall call it now). I'm stoked to get it back and toss it on the truck.

I did find some oil residue on the IC pipes and inside the intercooler, going to drop it and shake it out to see just how much is in there, maybe my turbo seal rebuild wasn't all that it was cracked up to be. However no oil trail inside the compressor housing inlet or outlet ... /shrug ?

[Rx7man]

What is LPC?

[hakcenter]

lift to port closure or something of that nature

[Rx7man]

ahh... clear as mud to me now!  I do kinda get the idea though.