|
Post by naughtyfox on Sept 4, 2017 14:01:56 GMT
The Symptoms of Motors With Stuck Rings:
The piston rings fit into horizontal grooves in the pistons. The rings expand against the cylinder wall and seal the combustion chamber. This ensures that the engine maintains a consistent level of compression. Stuck piston rings are uncommon, but they do occur. There are two positions in whi ch the rings can get stuck. They can become stuck inside the piston grooves, or they can stick against the cylinder wall.
Seized Engine
If the rings are stuck against the cylinder wall, the crankshaft will not rotate. This condition usually happens when an engine has been sitting for a long time. The rings rust and bond to the cylinder wall. If an engine is seized, it is important to eliminate other causes, such as failed crankshaft bearings, or broken valve-train components, since these can also seize an engine. The typical solution to this condition is to pour penetrating oil into the cylinders. Over a period of days, the oil will usually free the stuck rings.ch the rings can get stuck. They can become stuck inside the piston grooves, or they can stick against the cylinder wall.
Low Compression
If the rings are stuck inside the ring grooves, they cannot seal the combustion chamber. A compression tester must be used to determine if each individual cylinder is maintaining compression equal to the others. Rings can become stuck in the ring grooves from a buildup of carbon on the piston. They can also break and remain in the ring grooves for many miles.
Gasoline in Oil
A ring that is stuck in the ring groove allows unburned gases from the combustion process to force their way into the lower parts of the engine. This results in the engine oil becoming saturated with these gases. If the engine oil has an odor of gasoline, it could indicate a stuck ring. Engines that are only used for short drives can also develop a gasoline smell to the oil. This is caused by the engine always being operated at a low internal temperature, and should not be confused with a stuck piston ring.
Increased Crankcase Pressure
The crankcase is vented to allow internal pressure to escape. This venting is handled by the PCV valve. When a stuck ring allows pressure to enter the crankcase, the PCV valve will become overwhelmed, and internal pressure will build. This results in oil being blown out of the PCV valve. Another clue to increased crankcase pressure is a dipstick that is continually being pushed up, away from the dipstick tube. In this case, the pressure has vented itself out of the dipstick tube.
|
|
|
Post by naughtyfox on Sept 4, 2017 14:11:25 GMT
|
|
|
Post by Mr Stabby on Sept 4, 2017 16:50:57 GMT
Compression test results: expected 600psi one pot was 510, the other 180. Head off. Head gasket in poor condition, probably blowing on one side. Bores are fine. Rings are stuck fast to both pistons. Valves been tested as I write this but apparently OK, might need lapping in. So 2 sets of rings plus various gaskets and a whole load of labour to get the engine back in. I feel relieved, should be on my way by the end of this week. Ooh, I'm trying to remember which Thunderboater it was who suggested sticky or broken piston rings.
|
|
|
Post by naughtyfox on Sept 4, 2017 16:57:49 GMT
Compression test results: expected 600psi one pot was 510, the other 180. Head off. Head gasket in poor condition, probably blowing on one side. Bores are fine. Rings are stuck fast to both pistons. Valves been tested as I write this but apparently OK, might need lapping in. So 2 sets of rings plus various gaskets and a whole load of labour to get the engine back in. I feel relieved, should be on my way by the end of this week. Ooh, I'm trying to remember which Thunderboater it was who suggested sticky or broken piston rings. Mrs Tabby: "You are looking in completely the wrong place. There is something wrapped around your propeller."
|
|
|
Post by thebfg on Sept 4, 2017 17:01:42 GMT
Ooh, I'm trying to remember which Thunderboater it was who suggested sticky or broken piston rings. Mrs Tabby: Â "You are looking in completely the wrong place. There is something wrapped around your propeller." to be fair he did. but he had seen the engine. but he can be this week's no prize champion
|
|
|
Post by TonyDunkley on Sept 4, 2017 17:32:21 GMT
Compression test results: expected 600psi one pot was 510, the other 180. Head off. Head gasket in poor condition, probably blowing on one side. Bores are fine. Rings are stuck fast to both pistons. Valves been tested as I write this but apparently OK, might need lapping in. So 2 sets of rings plus various gaskets and a whole load of labour to get the engine back in. I feel relieved, should be on my way by the end of this week. Ooh, I'm trying to remember which Thunderboater it was who suggested sticky or broken piston rings. It was some ill-informed twerp, anxious to parade how little he really knows about diesel engines, who convinced "ricco" last week that the engine could be repaired without lifting out. If you're still struggling to remember who it was, go and stand in front of a mirror. However, in light of ricco's earlier post (today), you now have yet another opportunity to air your expertise by explaining the likely, and/or possible reasons why a two-cylinder engine with enough compression left on one of it's cylinders to run, albeit not very well, refused to fire and/or run at all when some other like-minded genius from the local Vetus agents emptied a can of Easy Start into it.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Sept 4, 2017 17:39:06 GMT
Don't forget the air filter 🔨🔨🔨
|
|
|
Post by Mr Stabby on Sept 4, 2017 17:41:45 GMT
Ooh, I'm trying to remember which Thunderboater it was who suggested sticky or broken piston rings. It was some ill-informed twerp, anxious to parade how little he really knows about diesel engines, who convinced "ricco" last week that the engine could be repaired without lifting out. No, I said the fault could and should be diagnosed without the engine being lifted out and that the fault would be more easily diagnosed with the engine in situ. I also said that the timing would not have slipped on a geared engine without this having caused significant top end damage which would be readily apparent on removing the rocker box cover. I'm glad for Ricco that the engine is finally being repaired because he was a bit down in the dumps when I was with him, having been broken down for three weeks.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Sept 4, 2017 17:43:13 GMT
Ooh, I'm trying to remember which Thunderboater it was who suggested sticky or broken piston rings. It was some ill-informed twerp, anxious to parade how little he really knows about diesel engines, who convinced "ricco" last week that the engine could be repaired without lifting out. If you're still struggling to remember who it was, go and stand in front of a mirror. However, in light of ricco's earlier post (today), you now have yet another opportunity to air your expertise by explaining the likely, and/or possible reasons why a two-cylinder engine with enough compression left on one of it's cylinders to run, albeit not very well, refused to fire and/or run at all when some other like-minded genius from the local Vetus agents emptied a can of Easy Start into it. If he is still with us the person who came up with easy start wants publicly flogging. As I mentioned before, for tired poor stating diesels the answer is a blow torch up the intake, not a hydraulic locking can of antiperspirant.
|
|
|
Post by TonyDunkley on Sept 4, 2017 18:24:31 GMT
It was some ill-informed twerp, anxious to parade how little he really knows about diesel engines, who convinced "ricco" last week that the engine could be repaired without lifting out. I also said that the timing would not have slipped on a geared engine without this having caused significant top end damage which would be readily apparent on removing the rocker box cover. Well done, there's some more ill-informed tripe for the general amusement, and a good illustration of just how worthless a smattering of knowledge such as yours really is. Your statement re. top end damage certainly holds good for mistimed valve opening on small indirect injection engines with very limited clearances between valves and piston crowns, but this particular model of Mitsubishi engine has a separate, second, gear-driven camshaft serving the flange mounted injection pump - the significance of which would seem to have completely escaped both you and the other clown with the Easy Start ! With incorrect (injection) timing as one of the likely/possible causes/contributory factors for the breakdown, the injection timing being very inaccessible and virtually impossible to check, and/or adjust, with the engine in situ, and the severe loss of compression on only one cylinder, which amongst other faults, was discovered/diagnosed by me a week ago on Bank Holiday Monday, removal of the engine at that stage was the only sensible and practical way to proceed.
|
|
|
Post by TonyDunkley on Sept 4, 2017 18:56:02 GMT
It was some ill-informed twerp, anxious to parade how little he really knows about diesel engines, who convinced "ricco" last week that the engine could be repaired without lifting out. If you're still struggling to remember who it was, go and stand in front of a mirror. However, in light of ricco's earlier post (today), you now have yet another opportunity to air your expertise by explaining the likely, and/or possible reasons why a two-cylinder engine with enough compression left on one of it's cylinders to run, albeit not very well, refused to fire and/or run at all when some other like-minded genius from the local Vetus agents emptied a can of Easy Start into it. If he is still with us the person who came up with easy start wants publicly flogging. As I mentioned before, for tired poor stating diesels the answer is a blow torch up the intake, not a hydraulic locking can of antiperspirant. Yes, . . . I've never known warming the intake air to fail to get a reluctant diesel going. The old method of doing it on tired old Listers, Petters, Nationals, and Gardners etc on commercials was by setting fire to a piece of paraffin or diesel soaked rag held near the air intakes on a length of wire, which, when all's said and done is really just a rough and ready variation on the 'Thermostart' cold starting aid found on so many of Perkins older models.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Sept 4, 2017 19:27:54 GMT
If he is still with us the person who came up with easy start wants publicly flogging. As I mentioned before, for tired poor stating diesels the answer is a blow torch up the intake, not a hydraulic locking can of antiperspirant. Yes, . . . I've never known warming the intake air to fail to get a reluctant diesel going. The old method of doing it on tired old Listers, Petters, Nationals, and Gardners etc on commercials was by setting fire to a piece of paraffin or diesel soaked rag held near the air intakes on a length of wire, which, when all's said and done is really just a rough and ready variation on the 'Thermostart' cold starting aid found on so many of Perkins older models. The Termostart on dads 4.108 in his Elysian has packed up, bit of wiring issue that needs resolving, I furnished him with a small blowlamp and firm instructions not to go near it with a can of fecking easy start on the pain of death! The perky only needs a sniff of heat if the temperature is single figures or below. It's on my growing list of his to do jobs, including removing the injector pump with a fuel leak on the govenor housing which is a bit inaccessible due to the neat packaging of the heat exchangers, manifold and associated pipework of a proper Perkins marine engine installation. Oh well, one job, ten jobs, it doesn't matter all that much in the grand scheme of things!
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Sept 4, 2017 20:08:42 GMT
Terrific that ricco is getting some assistance.
I hope he is up and running again quickly.
Rog
|
|
|
Post by TonyDunkley on Sept 4, 2017 20:33:24 GMT
Yes, . . . I've never known warming the intake air to fail to get a reluctant diesel going. The old method of doing it on tired old Listers, Petters, Nationals, and Gardners etc on commercials was by setting fire to a piece of paraffin or diesel soaked rag held near the air intakes on a length of wire, which, when all's said and done is really just a rough and ready variation on the 'Thermostart' cold starting aid found on so many of Perkins older models. It's on my growing list of his to do jobs, including removing the injector pump with a fuel leak on the govenor housing which is a bit inaccessible due to the neat packaging of the heat exchangers, manifold and associated pipework of a proper Perkins marine engine installation. It's likely that new seals in the throttle housing will cure the leak on a marine engine, but occasionally it turns out that the spindle bore in the ally throttle housing itself wears beyond the point where new seals alone will do the job. If there is much detectable side play/clearance of the spindle in the housing then it's well worth tracking down and fitting a new or good used one. As a vehicle engine, subject to far more numerous and extensive throttle operations/movements than a boat engine, the 4.108's that Ford used in the early Transits were well known for leaking fuel from badly worn pump throttle housings after covering fairly high mileages.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Sept 4, 2017 20:54:37 GMT
It's on my growing list of his to do jobs, including removing the injector pump with a fuel leak on the govenor housing which is a bit inaccessible due to the neat packaging of the heat exchangers, manifold and associated pipework of a proper Perkins marine engine installation. It's likely that new seals in the throttle housing will cure the leak on a marine engine, but occasionally it turns out that the spindle bore in the ally throttle housing itself wears beyond the point where new seals alone will do the job. If there is much detectable side play/clearance of the spindle in the housing then it's well worth tracking down and fitting a new or good used one. As a vehicle engine, subject to far more numerous and extensive throttle operations/movements than a boat engine, the 4.108's that Ford used in the early Transits were well known for leaking fuel from badly worn pump throttle housings after covering fairly high mileages. Likely as not it is only the seal, the engine hasn't done a lot of work. This is the best pump side photo I can find if a Perkins 4.108M lowline - it's identical to dad's. The thought of trying to do the seal laying on my stomach insitu is too much to contemplate! It's easier to get the pump off rather than fight with it mounted under the manifold and all that plumbing I shall go armed with spare nuts as it's almost inevitable I'll drop one in the depths if i don't! Credit to Roy's blogspot! royckdboats.blogspot.co.uk/2012/03/perkins-4108-marine-diesel-engine.html?m=1
|
|