compression test with weird results
Thread Starter
|
Senior User
Joined: Jan 2005
Posts: 222
Likes: 0
From: pennsburg Pa
compression test with weird results
I have a 95 f-350 7.3 that the engine was shot so i got a 97 psd to swap i got it in and had a bunch of switching parts over and such to get everything to work. I rebulit injectors new glow plugs, icp, pretty much everything but the internals. I didnt pull the heads but was out of a running van that had 130k "so he says ha" I got it in and all hooked up and after bleeding everything it fired and ran good but i noticed a slight tic out of the drivers valve cover but nothing abnormal really. No colored smoke out of the exhaust everything seemed good. Revs up good also. But to confirm everything was good inside the engine i bought a compression test from napa and i tried it today the first cylinder was 200 psi and the next 4 i tested were 0 psi so i didnt even try the others. Im not sure but i think the gauge must be shot since it runs fine but the test would make u think otherwise. I didnt drive it on road yet since front end is still off. You guys have any thoughts.
Senior User
Joined: Oct 2005
Posts: 400
Likes: 0
From: Jeffersonville IN
Did u get a gage that is good for at least 400psi? If not u probably blew the gage. Most used PS engines will be above 300-350 psi. U need a compression gage for diesels due to the higher compression ratio. Think the Power Stroke is line 17to1 ratio.Hope this helps.
Postmaster
Joined: Feb 2004
Posts: 3,266
Likes: 0
From: Levittown
so i got a 97 psd to swap i got it in and had a bunch of switching parts over and such to get everything to work. I rebulit injectors new glow plugs, icp, pretty much everything but the internals. I didnt pull the heads but was out of a running van that had 130k "so he says ha"
Bill
Thread Starter
|
Senior User
Joined: Jan 2005
Posts: 222
Likes: 0
From: pennsburg Pa
The engine was out of a 97 e350 van, its a 96 production date on the engine though, does any of this make a differance? All i know is theres alot differant from the van engine to a truck engine i had a lot of switching over to do.
Trending Topics
Hotshot
Joined: Jun 2007
Posts: 10,008
Likes: 7
From: Austin, TX
i would say your guage busted. not sure what brand that guage was, but i would get a snap on compression tester or something like that. surely it has to have plenty of compression if it runs good and doesn't miss out real bad. 4 dead holes would make for a very bad running, missing engine
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Postmaster
Joined: Feb 2004
Posts: 3,266
Likes: 0
From: Levittown
You are running split inj's on single programming (pcm).
Did you also remove the fuel damper?
"damper is mounted between the fuel pump and heads"
Bill
Thread Starter
|
Senior User
Joined: Jan 2005
Posts: 222
Likes: 0
From: pennsburg Pa
Bill thanks for helping, I dont believe i removed the fuel damper since i dont really know what it is ha. As far as the pcm is it ok to leave the computer in or what should i do get a 97 pcm? my trucks a 5 speed does that make a differace in the pcm from a van that would be auto? thanks Phil
Hotshot
Joined: Jun 2007
Posts: 10,008
Likes: 7
From: Austin, TX
5 speed PCMs have different fueling characteristics so i would get a PCM for a '97 w/ a 5 speed. the 5 speed PCM is programmed so that when you start letting off the clutch it will fuel the truck a little so you can take off at idle without giving it any go pedal.
Thread Starter
|
Senior User
Joined: Jan 2005
Posts: 222
Likes: 0
From: pennsburg Pa
So does all 97s have split shot if i get a pcm from a 97 pickup? will this make the truck run different, i havent started it alot of times yet but the couple times i did i had to warm the glow plugs a bunch of times before it fired,Will this diff pcm make so differance? the glow plugs and relay are brand new to.
Thread Starter
|
Senior User
Joined: Jan 2005
Posts: 222
Likes: 0
From: pennsburg Pa
just an update i should not have a fuel damper since i replaced the fuel pump and was the exact same as my 95's should i pull the valve covers to confirm i have split shot or single shot injectors?
