Just bought 2007 Glastron 185 GT in near-new condition, very lightly used. Engine looks mint, but I can't get it running properly and have been fighting various issues for three months now. It only ran fine for the first two hours or so, then it's a problem after problem. The symptoms are:
1. Engine runs rough, spazzing erratically, at any RPM.
2. Bogs down and stalls when given full throttle fast. Have to ease into it slowly.
3. Loss of power - can't plane it with three adults or more. With just myself planes in about 10 seconds. (should be 4 max!)
4. Possibly, excessive circ water pressure - raptured circ pump hose, flodded bilge etc.
5. Stalls easily at idle or when in gear at low RPM - have to give some throttle to keep running.
Cronology:
Took it out for the first time in April, for a couple hours or so. Everything went fine.
Next time I noticed that my engine is starting to run hot when on plane @ 3000RPM or more. Had to come off plane and it would instantly cool off. I brought it home and started digging: inspected raw water pump - brand new; took off exhaust riser - brand new, no rust; manifold - brand new; checked all hoses - brand new, no debree, stern hoses - brand new, no cracks. Then I decided to fabricate a different restrictor plate and machine the riser to allow 2x more water to pass through the riser. That seem had fixed my overheat issue.
Took the boat out again - the boat ran fine, no overheating, but at the end of my trip I noticed that the engine started to run a bit rough, on-and-off kind of thing. I decided to ignore it.
Next time I launched the boat - it ran rough from the beginning, and, once in a while, it would suddenly run fine for 2-5 seconds or so, and then back to running rough
. This is when the engine started to stall out on idle and I had to throttle it a little to keep the engine running, very difficult to maneuvre on low RPM. I brought it home and started digging: emptied the gas tank and filled with fresh gas. Tested and gapped spark plugs, tested spark plug cables - all good; took apart and cleaned distributor, cleaned and rang out ignition coil - all good.
None of this helped.The boat ran, but it was gutless. barely planing.
Then I went on a 50km trip, fuel efficiency and performance is almost as specked, 30m/h(50km/h) @3500RPM, about 8 GPH in fuel efficiency. On my way back, just before the marina, I decided to "floor it" and put the engine full throttle (4000RPM) for a couple of minutes. This is when my circ pump hose raptures :doh: Not cracks and leaks - raptures in half long way, flods the bilge, shorts out my electrical etc.
What a sh*t show! :facepalm: Barely docked the boat and dried it.
Then I started thinking that the head gasket is letting combustion gasses into the cooling water, causing excessive pressure and, suddenly, all pieces of the puzzle in my head started to fall into places. I decided to prove that it is, in fact, a head gasket:
I checked the engine oil - oil is nice and clean, no milk, no water. Check.
Then I decided to do the compression test - all 4 cylinders are at 160PSI (give or take 2PSI) on cold engine. Check.
Then I've noticed that the spark plugs on cylinders 1 & 4 are a bit wet mostly cylinder 4. Weird. Let's take off the manifold! Manifold itself is nice and clean, but I did notice a soot buildup in exhaust port 4 and just a bit in port #1, but mostly #4:
It appears that the the cylinders 2&3 burn nice and clean, no soot at all, the exhaust ports are clean and dry, with minimum carbon buildup. However, port 4 is quite bit contaminated and now I'm trying to determine what causes this buildup. Cylinder #1 also has some soot, but it's barely noticeable. Any ideas what could possibly cause this?
:help: :Cry:
1. Engine runs rough, spazzing erratically, at any RPM.
2. Bogs down and stalls when given full throttle fast. Have to ease into it slowly.
3. Loss of power - can't plane it with three adults or more. With just myself planes in about 10 seconds. (should be 4 max!)
4. Possibly, excessive circ water pressure - raptured circ pump hose, flodded bilge etc.
5. Stalls easily at idle or when in gear at low RPM - have to give some throttle to keep running.
Cronology:
Took it out for the first time in April, for a couple hours or so. Everything went fine.
Next time I noticed that my engine is starting to run hot when on plane @ 3000RPM or more. Had to come off plane and it would instantly cool off. I brought it home and started digging: inspected raw water pump - brand new; took off exhaust riser - brand new, no rust; manifold - brand new; checked all hoses - brand new, no debree, stern hoses - brand new, no cracks. Then I decided to fabricate a different restrictor plate and machine the riser to allow 2x more water to pass through the riser. That seem had fixed my overheat issue.
Took the boat out again - the boat ran fine, no overheating, but at the end of my trip I noticed that the engine started to run a bit rough, on-and-off kind of thing. I decided to ignore it.
Next time I launched the boat - it ran rough from the beginning, and, once in a while, it would suddenly run fine for 2-5 seconds or so, and then back to running rough
. This is when the engine started to stall out on idle and I had to throttle it a little to keep the engine running, very difficult to maneuvre on low RPM. I brought it home and started digging: emptied the gas tank and filled with fresh gas. Tested and gapped spark plugs, tested spark plug cables - all good; took apart and cleaned distributor, cleaned and rang out ignition coil - all good.None of this helped.The boat ran, but it was gutless. barely planing.
Then I went on a 50km trip, fuel efficiency and performance is almost as specked, 30m/h(50km/h) @3500RPM, about 8 GPH in fuel efficiency. On my way back, just before the marina, I decided to "floor it" and put the engine full throttle (4000RPM) for a couple of minutes. This is when my circ pump hose raptures
:doh: Not cracks and leaks - raptures in half long way, flods the bilge, shorts out my electrical etc.
What a sh*t show! :facepalm: Barely docked the boat and dried it.
Then I started thinking that the head gasket is letting combustion gasses into the cooling water, causing excessive pressure and, suddenly, all pieces of the puzzle in my head started to fall into places. I decided to prove that it is, in fact, a head gasket:
I checked the engine oil - oil is nice and clean, no milk, no water. Check.
Then I decided to do the compression test - all 4 cylinders are at 160PSI (give or take 2PSI) on cold engine. Check.
Then I've noticed that the spark plugs on cylinders 1 & 4 are a bit wet
mostly cylinder 4. Weird. Let's take off the manifold! Manifold itself is nice and clean, but I did notice a soot buildup in exhaust port 4 and just a bit in port #1, but mostly #4:
It appears that the the cylinders 2&3 burn nice and clean, no soot at all, the exhaust ports are clean and dry, with minimum carbon buildup. However, port 4 is quite bit contaminated and now I'm trying to determine what causes this buildup. Cylinder #1 also has some soot, but it's barely noticeable. Any ideas what could possibly cause this?
:help: :Cry:
