I posted a few weeks ago about this truck (7.3L No Start) and that owner has since sold the truck but it seems to be following me wherever I go .

So the current owner comes over today and says, "I want you to
change the injector o-rings in this truck, I'm sure that is causing the smoke".

So I told him how much it would cost him to change the o-rings and I also said that because of other symptoms that I have run into while working on the truck before, that I would reccomend doing a compression test.

He said, "When can I bring it over" So he is bringing it to me on friday morning.

My main question is: How do I find something to go in the glow plug hole to hook up to the compression gauge?

Any help or pointers would be greatly appreciated!


P.S. I guess I should give you all the symptoms.

Excessive smoke at startup, followed by a light haze while driving, moderate blowby, with a little pressure out of the filler neck.
It also does not start as quickly as it should. It takes about 50% more cranking time to start than a solid Powerstroke does.

 

Use an old drilled out glow plug ,may need to weld it to a reg tester .

 

does it "puff" out of the oil filler or a solid stream??? there are adapters for the glow plug hole out there. something like this...

 

It kinda goes puff, puff, puff


Thanks for the info. I would like to find an adapter, but I will do what I have to I guess.

 

puffing blowby from the oil fill means you will probably find a problem when you do a compression test...

 

I was afraid of that.

I read that compression should be 26-440 Psi. Is that correct?

And if the compression is low, are there any alternatives to replacing/rebuilding?

The truck has 157,000 miles on it.

 

26 to 440 sounds way off. You might want to look into that futher.

From what I have heard 157k is nothing for our trucks. If the compression is not within specs with 157 on it some thing is very wrong like maybe coolant getting into the oil.

 

Edit: 260-440psi. sorry my mistake.

157,000 miles should be just getting broken in, but this one seems like maybe it has had very poor if any maintanance.

I also think it has a chip in it, so that could be contributing to premature wear.

Is it possible that there chould be a bent push rod? will I be able to see it when I have the valve covers off?

Thanks guys, the help is greatly appreciated!!

 

You won't be able to tell if it has a bent pushrod without taking them out of the motor. You can hardly see any of it with just the valve cover off.

 

I think with compression less than 300 psi means she's worn out.

 

Compression should be 400 plus or minus 10%. Might be lower but you are mainly looking for close to 400 or all cylinders being within 10% of each other. You symptoms list certainly points at a compression issue.
The adapter in that picture is what I use with my compression tested but a GP can be adapted as well.

 

Thanks everbody,

I just ordered injector o-rings from Jim at rosewood diesel (I know that this is probably not the problem, but the customer wants me to change them)

That sounds more ligitimate than 260-440psi. Thanks Tim!

If he has low compression in 1 cyl. which is what I suspect, (no.7) is there any alternative to rebuilding?

Thanks again,

 

One cylinder down could be a broken ring, whole in piston or worn cylinder. Really no way to tell until the head is off and get an eyeball and measurements. Also be sure to try a leak down test with the valves closed to rule out a burned valve.

 

X2

A leak down test will tell you exactly where the problem is (other than a bent rod)

May even be a loosely fit injector

 

Thanks for all the input.

I just ordered a compression tester that will work in the glow plug hole from my local napa store, it will arrive tommorow.

I will be posting with progress-more likely questions !!! as I get into the project. The owner of this truck has another 7.3L (2002 4x4 CC SB Auto) that he claims has 380 horsepower with just a chip and a shift kit HAHAHA!!!! but, oh, I'm rambling.

My plan is to remove the VC and all of the other necassary parts, do a compression test, leak down test, etc.....

BTW, excuse my ignorance, but does anyone have any info on doing the leakdown test???