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Compression test!

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Old Apr 12, 2011 | 05:36 PM
  #16  
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bulla
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Well I bought a diesel kit from harbor freight and it's actually got the glo plug look alike fitting, meaning it looks like it will seat just like a glo plug would. Nice thing about it is it was only $30! And it fits many other applications. I'm anxious. The kit says to warm engine up to operating temp, is it necessary? I'd hate to have to put it alllll back together! Maybe I could try it before and after?
 
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Old Apr 12, 2011 | 05:52 PM
  #17  
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yes it must be warmed up
 
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Old Apr 12, 2011 | 06:51 PM
  #18  
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Just finished warming
It up! Thanks!
 
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Old Apr 12, 2011 | 08:24 PM
  #19  
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Ahh man! What a flop. I'm sure you guys new when I said the kit had the fitting some of you smiled and snickered and said to your self, no it doesn't! Cause the fitting it had was right I just couldn't tighten it cause the nut was a lil bigger and also there was no way to couple the quick connect to the fitting. Heck with it, I'm driving it for a few days till I round up the fittings to finish the comp test. Might take you up on that offer Al.
 
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Old Apr 12, 2011 | 09:13 PM
  #20  
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Originally Posted by Mike F250
Just for clarity, use teflon tape on the adapter that screws into the GP hole?
No the teflon is on all the other fittings, the fitting that screws into the GP hole is O-ring boss, so it uses an O-ring to seal.
 
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Old Apr 12, 2011 | 09:15 PM
  #21  
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Originally Posted by bulla
Ahh man! What a flop. I'm sure you guys new when I said the kit had the fitting some of you smiled and snickered and said to your self, no it doesn't! Cause the fitting it had was right I just couldn't tighten it cause the nut was a lil bigger and also there was no way to couple the quick connect to the fitting. Heck with it, I'm driving it for a few days till I round up the fittings to finish the comp test. Might take you up on that offer Al.
Yes it does come with a 10MM X 1MM fitting, but thats the difficult part is threading it into the GP hole.
 
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Old Apr 16, 2012 | 05:44 PM
  #22  
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just joined.. doing a comp test...

Nice thread and thx to all!

I just joined the forum and am getting some real good info here.

I have a 2000 7.3 with 278,000 miles on it. I have never done a compression test but am about to go get the fittings BigAlPSD recommended. I have the harbor freight kit but the adapter doesn't make it past the rocker arms.

I don't have any blow by, but my truck isn't running well. I've replaced the injectors three years ago, but I believe they might be bad again. I ran veg oil with a heated fuel system but the pressure kept dropping. Does low fuel pressure lead to injector failure? I think i read somewhere that it does.

I figured that I would run a compression test to get to know my engine better and start from there. If the compression is ok then I was going to get another set of injectors.

Also I have contribution failure on cylinders 5 and 8. It has been this way for 3 years.

My truck trembles at low rpms. It seems that it may be starving for fuel. Not sure though. I got my last set of injectors from Pensicola Diesel. I have a pressure gauge and see that my veg system isn't giving the 55 psi to the engine.

Any ideas? I am still trying to figure out how to edit my profile... FYI.

Thanks a bunch!
 
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Old Apr 16, 2012 | 05:54 PM
  #23  
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Compression is a good thing to know before diving in too deep. Good thinking on "Getting to know" your engine.

Ford spec I believe is 52PSI, below the injectors would start to score after extending periods of low PSI, from the lack of lubrication from the fuel.

I have no personal experience with Pensacola Diesel, but have not heard great things as far as 7.3 injectors go. FullForce(Casserly), Rosewood or Swamps(who has a 5 year warranty now) are the usual recommendations, and have great reputations. I personally run Casserly.

Although I do believe any of these builders warranties are voided when running alternative fuels FYI.
 
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Old Apr 16, 2012 | 06:08 PM
  #24  
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Thanks for the headz up BigALPSD!

Honestly I have been through 3 sets of injectors over the past 6 years. Each time its been my own fault. Either low fuel pressure, running out of fuel, or bad veg oil.

I am hoping that i just need some new injectors. Thanks to your post on the O-ring adaptor, I will be getting the part tomorrow and test the engine out.

bummed I have to warm it up first! Going have to work fast!

Seems like I understand the procedure now.
-Warm engine
-remove all glow plugs
-install comp tester
-4-5 cranks on each cylinder
- repeat for each cylinder 4-5 times.

Sound right?

I just tried posting some pics. Hope they come through!
 
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Old Apr 16, 2012 | 06:33 PM
  #25  
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Yeah the procedure sounds about right, you could get a good idea cold to point to any obvious issues, but for the health check of compression warm engine would be best. Also I can't take credit for the parts and ideas, actually got those from Joe(CSIPSD) but sharing ideas an d information is what forums are about.
 
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Old Apr 16, 2012 | 07:52 PM
  #26  
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i have seen where a guy had the harbor freight kit and he put a 8" 1/4" pipe on the end to extend the adapter. that may work with yours and be cheaper.
 
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Old Apr 16, 2012 | 09:31 PM
  #27  
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Good luck. Mine when i finally tore it down had .005 to .004 taper wear in each cylinder so the engine was worn out.
 
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Old Apr 17, 2012 | 11:00 AM
  #28  
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vegtoph
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Originally Posted by snakedoc
i have seen where a guy had the harbor freight kit and he put a 8" 1/4" pipe on the end to extend the adapter. that may work with yours and be cheaper.
I checked out this option this morning... I am a bit nervous about it. The NPT only catches about three threads.. I am afraid that the compression may blow out the threads. I don't want to take that gamble...

I am having a hard time finding that boss o-ring fitting locally. I have a few other places to check. Hope I can find it! The Snap-on truck was at the neighbors shop yesterday! I missed the boat!
 
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Old Apr 17, 2012 | 04:59 PM
  #29  
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What is locally(Where are yo located)? If you have a hydraulic fitting shop close they are relatively common or you could order from an online supplier.
 
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Old Apr 17, 2012 | 06:09 PM
  #30  
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vegtoph
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From: Worcester Massachusetts
well...

I got the fitting in Webster Ma. I am in Worcester Ma. I connected it to a 1/8 inch pipe to extend it. But the pipe is hitting the rocker arm!

I just warmed up my engine and now its cooling. Do you think that it will be warm enough if I leave the block heater plugged in over night? What a pain in the butt to put it all back together and have to warm it up.

I bought a set of reman injectors locally. about $200 a piece. I figured that even if I have low compression, I will run these new injectors. I have good reason to believe that bad veg has led to bad injectors.

BigAlPDS... do you have a pic of the end of the fitting M10 on the wip? my M10 fitting is female 1/8 npt. Does that thread onto the wip...? 1/8 male npt?

Thanks to all for the advice and help!
 
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