Diesel compression tester
- Thread starter spock500
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spock500
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Top man, good point will try that later :bannana:
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spock500
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Start of delivery is 15 degrees BTDC, all of the others brimmed on their delivery cycle as well.
Another thing to tick off the list
Another thing to tick off the list
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spock500
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Progress update;
Comp tester duly arrived this morning and off I went into the garage..
Tested all five cylinders using the dummy injector socket then two cylinders using the dummy glow plug.
Result, nothing, not a dickie bird didn't even move the needle on the gauge - put my bike pump on and managed to get it up to 8psi before it blew one of the connections on the pump.
Haynes rec a whopping 29 - 35 bar so i am a tad short of that.
Next step, head off (again) can do this in my sleep
Comp tester duly arrived this morning and off I went into the garage..
Tested all five cylinders using the dummy injector socket then two cylinders using the dummy glow plug.
Result, nothing, not a dickie bird didn't even move the needle on the gauge - put my bike pump on and managed to get it up to 8psi before it blew one of the connections on the pump.
Haynes rec a whopping 29 - 35 bar so i am a tad short of that.
Next step, head off (again) can do this in my sleep
Number_Cruncher
Active Member
Steady on.
Before you take the head off, it's best to have an idea what you're looking for first. Remember, you've had the head off before, and you haven't seen a problem.
Set a cylinder to TDC on compression, and lock the crank. Take out all injectors or glow plugs, which ever is easier. Screw in an adapter from the compression tester, and blow some air in - see if you can find out where the air is escaping.
Down the exhaust, and the exhaust valve isn't closing;
Out of the inlet, and the inlet valve isn't closing
Out of an adjacent cylinder - the head gasket isn't sealing between cylinders
Out of the coolant reservoir - the head gasket is leaking into the coolant.
etc, etc,
>>didn't even move the needle on the gauge
That's a bit odd though - you usually see something. Tell us exactly what you did - what you removed, what you fitted, etc, etc.
Before you take the head off, it's best to have an idea what you're looking for first. Remember, you've had the head off before, and you haven't seen a problem.
Set a cylinder to TDC on compression, and lock the crank. Take out all injectors or glow plugs, which ever is easier. Screw in an adapter from the compression tester, and blow some air in - see if you can find out where the air is escaping.
Down the exhaust, and the exhaust valve isn't closing;
Out of the inlet, and the inlet valve isn't closing
Out of an adjacent cylinder - the head gasket isn't sealing between cylinders
Out of the coolant reservoir - the head gasket is leaking into the coolant.
etc, etc,
>>didn't even move the needle on the gauge
That's a bit odd though - you usually see something. Tell us exactly what you did - what you removed, what you fitted, etc, etc.
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spock500
Active Member
Basically I put the dummy injector in each cylinder and cranked it over a few times, then I did the same with the glow plug but also re-fitted the actual injectors to those pots.
As mentioned there has always been a 'fizz' from the inlet valve seals but this has been checked twice with cams/lifters in situ.
The cylinders were tested when the head was off last time using diesel poured in the cylinder and measuring the drain off time.
So that leaves the gasket but i will do as you suggest and see if i can spot the leak.
As mentioned there has always been a 'fizz' from the inlet valve seals but this has been checked twice with cams/lifters in situ.
The cylinders were tested when the head was off last time using diesel poured in the cylinder and measuring the drain off time.
So that leaves the gasket but i will do as you suggest and see if i can spot the leak.
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spock500
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ok, cams off and hand cranked it with cam shaft sprocket on a make shift spindle to stop it being dragged inside.
Only have two of the pots sealed with injector and glow plugs, no resistance at all it difficult to see where its hissing from really. Nothing visible from the outside, this also eliminates any possible contact from the lifters being over extended making the valves not seal properly.
Only have two of the pots sealed with injector and glow plugs, no resistance at all it difficult to see where its hissing from really. Nothing visible from the outside, this also eliminates any possible contact from the lifters being over extended making the valves not seal properly.
Dieselman
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- Peugeot 403 Convertible
Rings gummed up with veg oil.
You could try filling the cylinders with diesel and leave it standing for a week. Drain off and ensure there won't be hydraulic locking then go for it again.
Stick a tube down the oil return holes in the head and into your ear. I think you'll hear the hissing then from the crankcase.
You could try filling the cylinders with diesel and leave it standing for a week. Drain off and ensure there won't be hydraulic locking then go for it again.
Stick a tube down the oil return holes in the head and into your ear. I think you'll hear the hissing then from the crankcase.
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spock500
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Bit of good news chaps,
Heads off and gasket shows clear signs of breeching, the steel bands which circle each pot have fluid ingress across them with other parts being covered in oil.
This type of gasket is about half (or more) of the thickness of the multi layer jobbie, its just not sealing.
Just need to check the head is ok (it was skimmed a while back) and get another gasket
Heads off and gasket shows clear signs of breeching, the steel bands which circle each pot have fluid ingress across them with other parts being covered in oil.
This type of gasket is about half (or more) of the thickness of the multi layer jobbie, its just not sealing.
Just need to check the head is ok (it was skimmed a while back) and get another gasket
Most of the trucks i do at work have gone over to the multi layer tin gasket for improved longevity, also the new modded gasket for the rover k series is the same to stop its famous rep for blowing gaskets
Lynall
Lynall
Number_Cruncher
Active Member
>>its just not sealing.
When you re-fitted the head last time, did you check the length of the head bolts, or did you fit new ones?
When you re-fitted the head last time, did you check the length of the head bolts, or did you fit new ones?
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spock500
Active Member
When I had the head recond the first time it had all new bolts and multi layer gasket, second time the head came off I measured the bolts which were within tolerances of 2mm but fitted single layer gasket.
Measured again today and they are within 1mm of tolerance so should be ok.
Followed the torquing sequence to the letter but thinking about it the head was removed a third time and refitted using the same single layer gasket, although it was never started in between.
This probably added to its inability to seal properly.
Measured again today and they are within 1mm of tolerance so should be ok.
Followed the torquing sequence to the letter but thinking about it the head was removed a third time and refitted using the same single layer gasket, although it was never started in between.
This probably added to its inability to seal properly.
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spock500
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Ok, finally got to the bottom of what was wrong (at last 
The car has been standing for about 6 months while I got on with other jobs, during this time it seems the rings have stuck.
I did check for this when the head was off by pouring diesel into half the pot and timing how long it took to drain which seemed ok.
When the engine was reassembled it had good compression but after a bit of cranking it vanished
I couldn't understand then i remembered that during assembly i coated everything with oil for protection.
Squirted some into the inlet duct and it went from nothing to not being able to crank it over!
It almost started but the battery wasn't quite up to it even with a jump, i am going to try warming up the block just to get it going in the hope the rings will free themselves under the engine heat.
The car has been standing for about 6 months while I got on with other jobs, during this time it seems the rings have stuck.
I did check for this when the head was off by pouring diesel into half the pot and timing how long it took to drain which seemed ok.
When the engine was reassembled it had good compression but after a bit of cranking it vanished
I couldn't understand then i remembered that during assembly i coated everything with oil for protection.Squirted some into the inlet duct and it went from nothing to not being able to crank it over!
It almost started but the battery wasn't quite up to it even with a jump, i am going to try warming up the block just to get it going in the hope the rings will free themselves under the engine heat.
Dieselman
Banned
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- 34,199
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- Peugeot 403 Convertible
As long as you are sure the pistons aren't hydraulic locking can't you just tow the car to start it.
If it won't go during a tow it really needs stripping down.
If it won't go during a tow it really needs stripping down.
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spock500
Active Member
Is there nothing I can put down the bores and let soak overnight?
It's auto, not sure how to toe start one of those?
edit: I was thinking maybe biodiesel which is a very good solvent
It's auto, not sure how to toe start one of those?
edit: I was thinking maybe biodiesel which is a very good solvent
If it will turn over on the starter what about a bit of easystart?
Wait for people to say engines then wont start without it ever again, which is true if your engine is totally shagged but for a one off it will be fine.
I have used it over the years, also 24v start a 12v volt diesel spins it over at a fair whack, not recomended on yours as prob elec inj pump.
Lynall
Wait for people to say engines then wont start without it ever again, which is true if your engine is totally shagged
but for a one off it will be fine.I have used it over the years, also 24v start a 12v volt diesel spins it over at a fair whack,
not recomended on yours as prob elec inj pump.Lynall
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spock500
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Tried the easy start but seems worse with it, what tends to happen is after a full squirt of oil down the inlet it almost catches but then the diesel/easy start dissolves it and bosch back to square one.
I'll try some penetrating fluid in bore one overnight, then re-oil it in the morning before starting - gonna have to wait until Monday as I live in a small cul de sac and when she does go boy we are going to be smokey and the bandit without the bandit
I'll try some penetrating fluid in bore one overnight, then re-oil it in the morning before starting - gonna have to wait until Monday as I live in a small cul de sac and when she does go boy we are going to be smokey and the bandit without the bandit
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spock500
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Cried with laughter when I saw this looking for ether (just in case)
http://cgi.ebay.co.uk/ws/eBayISAPI....K:MEWAX:IT&item=380102189679#ebayphotohosting
looking for ether (just in case)
http://cgi.ebay.co.uk/ws/eBayISAPI....K:MEWAX:IT&item=380102189679#ebayphotohosting
I remember years ago sticking an inj pump on some huge merc camper van and somehow managing to get the pump 180 deg out it ran, but like a bag of sh~te, quick bit of research at the local diesel shop had it timed up and running as well as expected.
Iirc you had to line marks up then somehow retard or was it advance the pump a couple of teeth to get it right.
If it wont catch on easy start sounds to me like a timing problem.
Lynall
Iirc you had to line marks up then somehow retard or was it advance the pump a couple of teeth to get it right.
If it wont catch on easy start sounds to me like a timing problem.
Lynall
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spock500
Active Member
Thanks Lynall,
We had a compression tester hooked up and the first four pots didnt even register, the fifth was at 7bar way off the min of 18 needed.
Over the weekend put atf down the bores which you could hear squeezing past the rings into the sump oil when you cranked it by hand.
Tried heating the engine and using small amounts of engine oil down the bore but didnt work as heat made oil thin which wasnt able to breech the gap the rings normally fill.
I also bought some diff oil 90 weight which i put down the bores, good strong compression instantly returned but it was too late to whizz over on the starter (neighbours back home
I spoke with Graham at Ultra Parts (very helpful) just in case the above doesnt work, basically head off remove carbon lip and measure core wear.
If small then a quick hone should do it if not engine out for rebore but i will need to cost this out first.
We had a compression tester hooked up and the first four pots didnt even register, the fifth was at 7bar way off the min of 18 needed.
Over the weekend put atf down the bores which you could hear squeezing past the rings into the sump oil when you cranked it by hand.
Tried heating the engine and using small amounts of engine oil down the bore but didnt work as heat made oil thin which wasnt able to breech the gap the rings normally fill.
I also bought some diff oil 90 weight which i put down the bores, good strong compression instantly returned but it was too late to whizz over on the starter (neighbours back home
I spoke with Graham at Ultra Parts (very helpful) just in case the above doesnt work, basically head off remove carbon lip and measure core wear.
If small then a quick hone should do it if not engine out for rebore but i will need to cost this out first.
