I need every bit of top speed out of my V/P 5.7L AQ200d 280 outdrive.

[gfackrell]

Re: I need every bit of top speed out of my V/P 5.7L AQ200d 280 outdrive.

alright, I did the compression test.
This is how I did it:
Pulled all plugs, put the throttle at wide open, pulled the coil to distributor wire.
Cranked the engine 4 to 5 times, recorded the highest reading. The engine wasn't warmed up prior to the test.
Results are:
CYL 1: 72 psi
CYL 2: 66 psi
CYL 3: 72 psi
CYL 4: 65 psi
CYL 5: 63 psi
CYL 6: 45 psi
CYL 7: 63 psi
CYL 8: 62 psi

Pretty damn sure these are not the numbers I wanted to see. I thought a 350 was supposed to be in the mid 100's for psi.
thoughts?

 

[Maclin]

Re: I need every bit of top speed out of my V/P 5.7L AQ200d 280 outdrive.

Those numbers are from a recently rebuilt engine? Ouch. Looks like cam timing is off, or valves lashed too tight. Do a leakdown test on one or more of the cylinders to listen for the compression leak.

Numbers should be 150+, even not warmed up. And I do not think squirting oil in the cyliders would help numbers that low.

Was the battery fully charged, and the starter spinning fast?

 

[gfackrell]

Re: I need every bit of top speed out of my V/P 5.7L AQ200d 280 outdrive.

never done a leak down test. What is the procedure?

 

[Maclin]

Re: I need every bit of top speed out of my V/P 5.7L AQ200d 280 outdrive.

Cylinder leakdown test is done with the piston at TDC of compression stroke. Compressed air is introduced thru a sparkplug hole fitting, and then you listen for hissing air from the intake manifold, or exhaust, or crankcase. It is a standard test , you can google up the exact procedure with PSI recommendations and the like.

 

[Bondo]

Re: I need every bit of top speed out of my V/P 5.7L AQ200d 280 outdrive.

alright, I did the compression test.
This is how I did it:
Pulled all plugs, put the throttle at wide open, pulled the coil to distributor wire.
Cranked the engine 4 to 5 times, recorded the highest reading. The engine wasn't warmed up prior to the test.
Results are:
CYL 1: 72 psi
CYL 2: 66 psi
CYL 3: 72 psi
CYL 4: 65 psi
CYL 5: 63 psi
CYL 6: 45 psi
CYL 7: 63 psi
CYL 8: 62 psi

Pretty damn sure these are not the numbers I wanted to see. I thought a 350 was supposed to be in the mid 100's for psi.
thoughts?

Ayuh,.... "recorded the highest reading",..??..?? As in multiple tests,..??

My compression test gauge pumps up, to it's highest number,...

Yer not sayin' yer gauge, the needle just jumps up to a number, 'n returns to 0, each compression stroke are ya,..??

Somebody had that problem 'round here a few weeks ago,...

Like Maclin says, a buck fifty is healthy,...

Basically, 150 psi is a healthy motor,...
175 psi is a well built motor,...
125 psi is a motor gettin' tired,...
100 psi is a rebuildable core motor, 'n over 200 psi, you've got water in the cylinders...

 

[Don S]

Re: I need every bit of top speed out of my V/P 5.7L AQ200d 280 outdrive.

I would be checking my compression gauge before anything else. With those compression numbers you would be lucky to get it started, let alone get 4000 rpm out of it.

 

[gfackrell]

Re: I need every bit of top speed out of my V/P 5.7L AQ200d 280 outdrive.

Just did another test with a different gauge.
Results:
Cyl 1 -109
Cyl 2 - 100
Cyl 3 - 110
Cyl 4 - 97
Cyl 5 - 94
Cyl 6 - 85
Cyl 7 - 105
Cyl 8 - 102

 

[gfackrell]

Re: I need every bit of top speed out of my V/P 5.7L AQ200d 280 outdrive.

Ayuh,.... "recorded the highest reading",..??..?? As in multiple tests,..??

My compression test gauge pumps up, to it's highest number,...

Yer not sayin' yer gauge, the needle just jumps up to a number, 'n returns to 0, each compression stroke are ya,..??

Somebody had that problem 'round here a few weeks ago,...

Like Maclin says, a buck fifty is healthy,...

Basically, 150 psi is a healthy motor,...
175 psi is a well built motor,...
125 psi is a motor gettin' tired,...
100 psi is a rebuildable core motor, 'n over 200 psi, you've got water in the cylinders...

no, the needle stays at the top, getting a little higher for the first couple strokes. What the needle maxes out at is what I recorded.

 

[Don S]

Re: I need every bit of top speed out of my V/P 5.7L AQ200d 280 outdrive.

What happens if you put some oil in the cylinder, does the compression come up.

Have a look at this service bulletin on doing a compression test. The original bulletin was from GM and Volvo had one almost word for word, I just don't have the Volvo version.

View attachment 97-25 Compression Test.pdf

 

[gfackrell]

Re: I need every bit of top speed out of my V/P 5.7L AQ200d 280 outdrive.

What happens if you put some oil in the cylinder, does the compression come up.

Have a look at this service bulletin on doing a compression test. The original bulletin was from GM and Volvo had one almost word for word, I just don't have the Volvo version.

View attachment 170944

Nope,
Just did that and got the exact same readings on one side of the engine. (2468 cylinders)

 

[Don S]

Re: I need every bit of top speed out of my V/P 5.7L AQ200d 280 outdrive.

Read this and check your valve adjustment.

View attachment Adjusting Valves.pdf

 

[gfackrell]

Re: I need every bit of top speed out of my V/P 5.7L AQ200d 280 outdrive.

Read this and check your valve adjustment.

View attachment 170945

Don,

One quick question, In your write up it talkes about only adjusting the valve once, otherwise it will end up too tight. That sounds like what was done on my engine. How do I adjust them since they have already been adjusted once?

Thanks for the write up it's great.

Greg

 

[Don S]

Re: I need every bit of top speed out of my V/P 5.7L AQ200d 280 outdrive.

Remove the spark plugs, back the rocker arm nuts off so that all are too loose when the valve is closed. Then crank the engine over with the plugs out to build oil pressure. Then follow the write up.

 

[gfackrell]

Re: I need every bit of top speed out of my V/P 5.7L AQ200d 280 outdrive.

Don,

I did that, and got halfway thru adjusting the valves, and I seem to be putting them right back where they were, within a quarter turn. Just for kicks, I checked the compression on cylinder 6 before turning the nuts back in, (figuring the valves couldn't be not seating if they were this loose) they were 1 turn from the previous adjustment, and I got 95 psi, where I was previously getting 85. I turned the nuts out two more turns and got up to 110 psi on this same cylinder 6. I'm no expert, but i'm pretty sure I'm following what's going on here. This shouldn't be happening should it? Could my problem be cam timing like previously mentioned?

Greg

 

[Tail_Gunner]

Re: I need every bit of top speed out of my V/P 5.7L AQ200d 280 outdrive.

You need to take that engine back to the builder....Ask him who's doing what right..with respect to CR and valve train.

 

[Don S]

Re: I need every bit of top speed out of my V/P 5.7L AQ200d 280 outdrive.

Impossible to say what's wrong, none of us can see it, hear it, feel it or otherwise know anything about it other than what you say.

Most of what a real tech does is by sight, sound, and smell, of the engine while running. It at least helps him look the right direction. We have none of that. With those compression readings, you have a junk engine. if it's been rebuilt, then they did a poor job of it.

 

[gfackrell]

Re: I need every bit of top speed out of my V/P 5.7L AQ200d 280 outdrive.

I finished adjusting the rest of the valves, and the readings all bumped up between 3 and 5 psi.
anything else you guys can recommend to check before calling the rebuilder? Which I can't do until monday anyway... The engine did come with a two year warranty, I guess I can pursue that. Would the engine run if the cam timing were off? What is the way to check the cam timing? Pull the timing cover off and line up the dots? I'm open to any more ideas if you have them. I'm willing to do whatever you guys suggest.
Thanks for all the help, I really appreciate the free advice.

 

[Tail_Gunner]

Re: I need every bit of top speed out of my V/P 5.7L AQ200d 280 outdrive.

Call him as Don said the engine is in a very bad state

 

[Maclin]

Re: I need every bit of top speed out of my V/P 5.7L AQ200d 280 outdrive.

You really need to stop working on it and let the builder work it on warranty, otherwise they will not know what all you did to it and could say you messed it up after it left the shop and warranty is void.

 

[Bondo]

Re: I need every bit of top speed out of my V/P 5.7L AQ200d 280 outdrive.

I finished adjusting the rest of the valves, and the readings all bumped up between 3 and 5 psi.
anything else you guys can recommend to check before calling the rebuilder? Which I can't do until monday anyway... The engine did come with a two year warranty, I guess I can pursue that. Would the engine run if the cam timing were off? What is the way to check the cam timing? Pull the timing cover off and line up the dots? I'm open to any more ideas if you have them. I'm willing to do whatever you guys suggest.
Thanks for all the help, I really appreciate the free advice.

Ayuh,.... How, Exactly are ya adjustin' the valves,..??