Any hints for tips, compression check on ford 330 sabres

Sorry Rob, no idea, but you do like to keep busy, as if building a new boat from scratch isn't enough!:):) I presume you're keeping the Sunseeker until the new one is complete?
 
Rob what are you intending to prove?

If you are looking for evidence of wear out highly unlikely, unless overheated, bores will be good, Fords generally pick up #6 sometimes #5 if motor has been cooked.

As far as I am aware no published #'s for compression and certainly no data available for doing the far more useful blow by test.

Serious advice although it does not sound like it. If you suspect engine damage the 'low earth test' will tell you...Warm engine though, and shut down, unscrew oil filler cap until just resting in rocker cover. Fire up, if filler cap enters low earth orbit you have picked up a piston, simple as that!

As you are well aware IF you have piston damage sadly time to walk away from motors due to unique pistons.

Good luck.
 
Just looking at a reason for starboard motor been lazy.
Curiosity as much as anything. It's always been the stbd that was suspect.
The head has been off that side and returned to sabre a long time ago, this I do know.
Thanks LS

Was more thinking valves than pistons, but I realises comp check won't differentiate one or the other
 
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Robg71 said:
Just looking at a reason for starboard motor been lazy.
Curiosity as much as anything. It's always been the stbd that was suspect.
The head has been off that side and returned to sabre a long time ago, this I do know.
Thanks LS

Was more thinking valves than pistons, but I realises comp check won't differentiate one or the other
Click to expand...

you can differentiate, pistons or valves, take reading as stated note the figures, then add oil to the bore if the reading is better then the bores are worn if no difference then the valves need regrinding or replacing. But as LS says a lot of "messing" about to fix a tired engine, we are waiting for our 180's to come to a grinding halt, they suffer from the same symptoms but refuse to stop.
 
I'm trying to help them not come to a grinding holt.
If it needs head work then lots of places that can do this. I imagine enough meat left in valve seats to be cut a couple of times if needed. the port side has higher oil pressure too. It may come to nothing.
Hopefully...
Part of my preventative maintenance on something that has been stood for so long really.
 
Robg71 said:
I'm trying to help them not come to a grinding holt.
If it needs head work then lots of places that can do this. I imagine enough meat left in valve seats to be cut a couple of times if needed. the port side has higher oil pressure too. It may come to nothing.
Hopefully...
Part of my preventative maintenance on something that has been stood for so long really.
Click to expand...

then get yourself a diesel engine cylinder pressure tester and go ahead.
 
Robg71 said:
Just looking at a reason for starboard motor been lazy.
Curiosity as much as anything. It's always been the stbd that was suspect.
The head has been off that side and returned to sabre a long time ago, this I do know.
Thanks LS

Was more thinking valves than pistons, but I realises comp check won't differentiate one or the other
Click to expand...


Put compressed air in cylinder and ear to inlet, exhaust and breather.

Make sure piston is at bdc.
 
Rob,

Diesel engines unless way over-fueled leading to them running 'mad ot' tend to give their valves a pretty easy time.

As I see it you want to see if you can detect what is different between your good v/s the lackluster engine using the good engine as a benchmark.

Problem with compression testing diesel engines are well known which is why pretty much all manufacturers abandoned the practice many years ago, think Detroit is the exception.

Let me give you one example, if the starter on one of your engines is real spunky and has faster cranking speed than its brother this will effect the readings you will likely get. Say this starter is on your poor engine range of compression #'s could be better on lame duck engines which will lead to a heap of head scratching.

Couple of thoughts.

You can do a comparative blow by test on engines which would involve far less spanner work with more a more definitive result.

Have you got a tapping on your exhaust risers, or can you tap them 1/8th NPT to fit a pyrometer probe, do a run with pyro on good engine and record EGT at WOT then repeat and record EGT on the other motor.

Just a thought is your lackluster engine running with gearbox running in astern position? Also what is difference in boost #'s between the engines.

If you wanted to run EGT's I can loan you the kit as I no longer chase around doing this stuff.

Good luck.
 
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Having just completed this exercise on my Volvo engine this week end my comments are:

“Do test with warm engine”
All well and good but the practicality of this is that it depends on what is involved in removing the injectors or glowplugs (depending on the procedure for the engine in question). Mine were well and truly corroded in and took several days work to extract all of them, destroying at least one in the process. The bores they were in will need work before reinstalling, which isn’t a problem for me as the head is coming off anyway. Anyway, just saying it was not as simple as it looked though I would imagine that if the engine had been better looked after by previous owners it may have been easier!!
You can still do the test with a cold engine but you only get out of it if the cylinders are even or not as I don’t think you would ever get the published values when cold.

“low orbit test”
Don’t think this applies if you have ventilated crankcase.

Have fun!!
 
dpb said:
Having just completed this exercise on my Volvo engine this week end my comments are:

“Do test with warm engine”
All well and good but the practicality of this is that it depends on what is involved in removing the injectors or glowplugs (depending on the procedure for the engine in question). Mine were well and truly corroded in and took several days work to extract all of them, destroying at least one in the process. The bores they were in will need work before reinstalling, which isn’t a problem for me as the head is coming off anyway. Anyway, just saying it was not as simple as it looked though I would imagine that if the engine had been better looked after by previous owners it may have been easier!!
You can still do the test with a cold engine but you only get out of it if the cylinders are even or not as I don’t think you would ever get the published values when cold.

“low orbit test”
Don’t think this applies if you have ventilated crankcase.

Have fun!!
Click to expand...

So what purpose of compression test if you are pulling head anyway?

Fords do not have cranky copper injector sleeves like Volvo, however does illustrate exactly why compression testing not a good practice' and that practice no longer recognised by majority of engine manufacturers.

Low earth orbit test.......A Cat 3126 sends the dipstick into low earth orbit as soon as piston picks up even with CCV.
 
Latestarter1 said:
So what purpose of compression test if you are pulling head anyway?

QUOTE]

To avoid the situation where I find and fix something obvious in one cylinder to find there is still a problem on reassembly with another that was for some reason not obvious.
This way I know what cylinder(s) are 'bad' and need problem(s) identifying and fixing.
Click to expand...
 
LS what is your view on injector servicing on sabre 150, done 5000 hours last lapped at 1000 hours. Smoke etc has hardly changed over the years, may be a little more than when younger, just a haze at low power none at high, no soot stains etc.

worthwhile, or wasting my money

Many thanks
 
david_bagshaw said:
LS what is your view on injector servicing on sabre 150, done 5000 hours last lapped at 1000 hours. Smoke etc has hardly changed over the years, may be a little more than when younger, just a haze at low power none at high, no soot stains etc.

worthwhile, or wasting my money

Many thanks
Click to expand...

What was the reason for lapping in nozzles at 1,000 hours?

Provided fuel system is kept fed with diet of clean fuel I would leave well alone. Majority of pump shops simply whack on new tips as they are so cheap, however I am paranoid about some of the aftermarket junk out there making it another reason for leaving alone.

Give the motor some real tight wire for an hour, part load haze should clean up.

Good luck



Com
 
Latestarter1 said:
Rob,

Diesel engines unless way over-fueled leading to them running 'mad ot' tend to give their valves a pretty easy time.

As I see it you want to see if you can detect what is different between your good v/s the lackluster engine using the good engine as a benchmark.

Problem with compression testing diesel engines are well known which is why pretty much all manufacturers abandoned the practice many years ago, think Detroit is the exception.

Let me give you one example, if the starter on one of your engines is real spunky and has faster cranking speed than its brother this will effect the readings you will likely get. Say this starter is on your poor engine range of compression #'s could be better on lame duck engines which will lead to a heap of head scratching.

Couple of thoughts.

You can do a comparative blow by test on engines which would involve far less spanner work with more a more definitive result.

Have you got a tapping on your exhaust risers, or can you tap them 1/8th NPT to fit a pyrometer probe, do a run with pyro on good engine and record EGT at WOT then repeat and record EGT on the other motor.

Just a thought is your lackluster engine running with gearbox running in astern position? Also what is difference in boost #'s between the engines.

If you wanted to run EGT's I can loan you the kit as I no longer chase around doing this stuff.

Good luck.
Click to expand...

dont think mine has a port to tap in to. I will have a look. I dont recollect one on the turbo outlet pipe. maybe on the manifold before the turbo...
The turbos do pull similar boost figures, just shy of 2 bar, but at different revs.
also one engine pulls nearly 2900 rpm, the other only to 26 if memory is correct. (Only done this very briefly) for similar boost gauge figures the morse controls have about an inch of difference between them from being level
 
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