Any one got the specs for a compression check on a 360 v8 '91 ?

I'm only getting 8 bar (~ 115 psi) pretty consistently across all cylinders.
I would have expected about 140-160 psi and am a bit surprised it is so
consisently low. That was a dry test - didn't do a wet one.

Dave Milne, Scotland '91 Wagoneer

 

Dave,

The first thing you are looking for is uniformity across all cylinders,
which you have. I wouldn't worry.

Earle

"Dave Milne" <jeep@_removethisbit_milne.info> wrote in message
news:8c7Wg.31235$r61.2601@text.news.blueyonder.co. uk...
> Any one got the specs for a compression check on a 360 v8 '91 ?
>
> I'm only getting 8 bar (~ 115 psi) pretty consistently across all
cylinders.
> I would have expected about 140-160 psi and am a bit surprised it is so
> consisently low. That was a dry test - didn't do a wet one.
>
> Dave Milne, Scotland '91 Wagoneer
>
>

 

Dave,

The first thing you are looking for is uniformity across all cylinders,
which you have. I wouldn't worry.

Earle

"Dave Milne" <jeep@_removethisbit_milne.info> wrote in message
news:8c7Wg.31235$r61.2601@text.news.blueyonder.co. uk...
> Any one got the specs for a compression check on a 360 v8 '91 ?
>
> I'm only getting 8 bar (~ 115 psi) pretty consistently across all
cylinders.
> I would have expected about 140-160 psi and am a bit surprised it is so
> consisently low. That was a dry test - didn't do a wet one.
>
> Dave Milne, Scotland '91 Wagoneer
>
>

 

Dave,

The first thing you are looking for is uniformity across all cylinders,
which you have. I wouldn't worry.

Earle

"Dave Milne" <jeep@_removethisbit_milne.info> wrote in message
news:8c7Wg.31235$r61.2601@text.news.blueyonder.co. uk...
> Any one got the specs for a compression check on a 360 v8 '91 ?
>
> I'm only getting 8 bar (~ 115 psi) pretty consistently across all
cylinders.
> I would have expected about 140-160 psi and am a bit surprised it is so
> consisently low. That was a dry test - didn't do a wet one.
>
> Dave Milne, Scotland '91 Wagoneer
>
>

 

Dave Milne wrote:
> Any one got the specs for a compression check on a 360 v8 '91 ?

Got me. 160 is "normal" for the I6, but it has a higher compression
rating than the V8.

> I'm only getting 8 bar (~ 115 psi) pretty consistently across all
> cylinders. I would have expected about 140-160 psi and am a bit
> surprised it is so consisently low. That was a dry test - didn't do a
> wet one.

Consistency (psi +- 10%) is what your looking for in a compression test.

- Run the engine till it gets warm to the touch.
- I find it easier on the battery with all the plugs out.
- Hold the throttle all the way open or the engine won't breathe.
- Cranking time varies, but most go with 5-10. I usually do 5.

FWIW, I do a compression test each time I change plugs. Except this
time, the hose on my compression tester sprang a leak. :( 160-165 is
what the I6 gets when warm.

--
DougW

 

Dave Milne wrote:
> Any one got the specs for a compression check on a 360 v8 '91 ?

Got me. 160 is "normal" for the I6, but it has a higher compression
rating than the V8.

> I'm only getting 8 bar (~ 115 psi) pretty consistently across all
> cylinders. I would have expected about 140-160 psi and am a bit
> surprised it is so consisently low. That was a dry test - didn't do a
> wet one.

Consistency (psi +- 10%) is what your looking for in a compression test.

- Run the engine till it gets warm to the touch.
- I find it easier on the battery with all the plugs out.
- Hold the throttle all the way open or the engine won't breathe.
- Cranking time varies, but most go with 5-10. I usually do 5.

FWIW, I do a compression test each time I change plugs. Except this
time, the hose on my compression tester sprang a leak. :( 160-165 is
what the I6 gets when warm.

--
DougW

 

Dave Milne wrote:
> Any one got the specs for a compression check on a 360 v8 '91 ?

Got me. 160 is "normal" for the I6, but it has a higher compression
rating than the V8.

> I'm only getting 8 bar (~ 115 psi) pretty consistently across all
> cylinders. I would have expected about 140-160 psi and am a bit
> surprised it is so consisently low. That was a dry test - didn't do a
> wet one.

Consistency (psi +- 10%) is what your looking for in a compression test.

- Run the engine till it gets warm to the touch.
- I find it easier on the battery with all the plugs out.
- Hold the throttle all the way open or the engine won't breathe.
- Cranking time varies, but most go with 5-10. I usually do 5.

FWIW, I do a compression test each time I change plugs. Except this
time, the hose on my compression tester sprang a leak. :( 160-165 is
what the I6 gets when warm.

--
DougW

 

Thanks Doug & Earle.

Dave

"DougW" <post.replies@invalid.address> wrote in message
news:MC8Wg.32151$iA5.14083@dukeread11...
> Dave Milne wrote:
> > Any one got the specs for a compression check on a 360 v8 '91 ?
>
> Got me. 160 is "normal" for the I6, but it has a higher compression
> rating than the V8.
>
> > I'm only getting 8 bar (~ 115 psi) pretty consistently across all
> > cylinders. I would have expected about 140-160 psi and am a bit
> > surprised it is so consisently low. That was a dry test - didn't do a
> > wet one.
>
> Consistency (psi +- 10%) is what your looking for in a compression test.
>
> - Run the engine till it gets warm to the touch.
> - I find it easier on the battery with all the plugs out.
> - Hold the throttle all the way open or the engine won't breathe.
> - Cranking time varies, but most go with 5-10. I usually do 5.
>
> FWIW, I do a compression test each time I change plugs. Except this
> time, the hose on my compression tester sprang a leak. :( 160-165 is
> what the I6 gets when warm.
>
> --
> DougW
>
>

 

Thanks Doug & Earle.

Dave

"DougW" <post.replies@invalid.address> wrote in message
news:MC8Wg.32151$iA5.14083@dukeread11...
> Dave Milne wrote:
> > Any one got the specs for a compression check on a 360 v8 '91 ?
>
> Got me. 160 is "normal" for the I6, but it has a higher compression
> rating than the V8.
>
> > I'm only getting 8 bar (~ 115 psi) pretty consistently across all
> > cylinders. I would have expected about 140-160 psi and am a bit
> > surprised it is so consisently low. That was a dry test - didn't do a
> > wet one.
>
> Consistency (psi +- 10%) is what your looking for in a compression test.
>
> - Run the engine till it gets warm to the touch.
> - I find it easier on the battery with all the plugs out.
> - Hold the throttle all the way open or the engine won't breathe.
> - Cranking time varies, but most go with 5-10. I usually do 5.
>
> FWIW, I do a compression test each time I change plugs. Except this
> time, the hose on my compression tester sprang a leak. :( 160-165 is
> what the I6 gets when warm.
>
> --
> DougW
>
>

 

Thanks Doug & Earle.

Dave

"DougW" <post.replies@invalid.address> wrote in message
news:MC8Wg.32151$iA5.14083@dukeread11...
> Dave Milne wrote:
> > Any one got the specs for a compression check on a 360 v8 '91 ?
>
> Got me. 160 is "normal" for the I6, but it has a higher compression
> rating than the V8.
>
> > I'm only getting 8 bar (~ 115 psi) pretty consistently across all
> > cylinders. I would have expected about 140-160 psi and am a bit
> > surprised it is so consisently low. That was a dry test - didn't do a
> > wet one.
>
> Consistency (psi +- 10%) is what your looking for in a compression test.
>
> - Run the engine till it gets warm to the touch.
> - I find it easier on the battery with all the plugs out.
> - Hold the throttle all the way open or the engine won't breathe.
> - Cranking time varies, but most go with 5-10. I usually do 5.
>
> FWIW, I do a compression test each time I change plugs. Except this
> time, the hose on my compression tester sprang a leak. :( 160-165 is
> what the I6 gets when warm.
>
> --
> DougW
>
>