My engine of choice is my EFNR Model 90. It starts with ease and pumps a good healthy pencil thickness of cooling water flow no problem at all. My problem is that if I run it for more than 20 - 30 mins the water flow reduces to nothing at all and if I haven't spotted that happening, the engine stops. Immediately after stopping, the engine turns freely so it hasn't seized. Left to cool a bit, it starts again but no coolant flow. Left to cool down completely it is OK again. I replaced the impellor and cleaned out the water feed pipe about 2 years ago with no change. I'm also fairly sure that I have had the head off this one and cleaned out the water jacket but I cannot be certain of this.
Any thoughts on what I could try?
Cheers
Steven
My EFNR stops pumping water - help!
Moderators: John@sos, charlesp, Charles uk, RickUK, Petergalileo
Tricky one.
Have not come across anything quite like this before, so lets look at this logically. ( ish! )
Failure of water circulating in such a simple system as that on a seagull can only be due to a blockage somewhere, a loose / mis aligned water pipe, reduced water supply or a failure of the impellor to pump sufficient water.
Firstly, you don't say if you are running the motor in a tank or not? you frequently get circulation problems in tanks, having said that my 90 will even pump at tickover when my 40+ won't, anyway if you are running in a tank try it on a suitable river ( but take a backup and / or oars obviously! ) the 'ram' effect of moving through the water and lack of swirling ofter improves things.
The next thing I would try is to get the motor to the point when the water stops and immediately backflush it to see if there is a blockage, that should tell you where to go next.
It is odd that it will run for so long, I mean it has obviously well reached operating temp by 20 mins!
I can only thing there is still some sediment or something in the system somewhere or perhaps the impellor is not quite in the correct position or is perhaps loose and moving?
Just ideas.
Have not come across anything quite like this before, so lets look at this logically. ( ish! )
Failure of water circulating in such a simple system as that on a seagull can only be due to a blockage somewhere, a loose / mis aligned water pipe, reduced water supply or a failure of the impellor to pump sufficient water.
Firstly, you don't say if you are running the motor in a tank or not? you frequently get circulation problems in tanks, having said that my 90 will even pump at tickover when my 40+ won't, anyway if you are running in a tank try it on a suitable river ( but take a backup and / or oars obviously! ) the 'ram' effect of moving through the water and lack of swirling ofter improves things.
The next thing I would try is to get the motor to the point when the water stops and immediately backflush it to see if there is a blockage, that should tell you where to go next.
It is odd that it will run for so long, I mean it has obviously well reached operating temp by 20 mins!
I can only thing there is still some sediment or something in the system somewhere or perhaps the impellor is not quite in the correct position or is perhaps loose and moving?
Just ideas.
Thanks for your thoughts Waggles.
I've never run it long enough in a tank for the problem to occur. I use it on Loch Lomond where there is little in the way of silt.
I wondered if my original steel tank had a blocked vent and it has a pin hole leak so I swapped it for a long range brass tank - same problem.
I didn't have the big rubber washers to fit between the brass tank and cylinder head and the fuel tank got quite hot along with the fuel!!! This couldn't have happened with the steel tank because it is not in direct contact with the cylinder head and I suffered the same problem with both tanks. It pumps water extremely well to start with.
I'm going to try back flushing first and if nothing disturbing comes out, I'll remove the gearbox and check the impellor and back flush again. Last job will be cylinder head removal.
Always open to other ideas though!
Cheers
Steven
I've never run it long enough in a tank for the problem to occur. I use it on Loch Lomond where there is little in the way of silt.
I wondered if my original steel tank had a blocked vent and it has a pin hole leak so I swapped it for a long range brass tank - same problem.
I didn't have the big rubber washers to fit between the brass tank and cylinder head and the fuel tank got quite hot along with the fuel!!! This couldn't have happened with the steel tank because it is not in direct contact with the cylinder head and I suffered the same problem with both tanks. It pumps water extremely well to start with.
I'm going to try back flushing first and if nothing disturbing comes out, I'll remove the gearbox and check the impellor and back flush again. Last job will be cylinder head removal.
Always open to other ideas though!
Cheers
Steven
What a fantastic place that must be to go seagulling! I am envious!
Your plan sounds good to me. I guess if it doesn't improve things you are possibly looking for a crack somewhere that is opening up once the motor has been hot for a while ( would have expected it to open a bit quicker than 20 mins to be honest though ) or maybe a joining face is a little out and a gasket is leaking when hot?
Although I haven't known of it I guess if cylinder pressure were to leak into the cooling system you would get a power loss ( hence the stopping ) and the pressure would probably over come the 'power' of the impellor and stop the water. As I say, just an idea, perhaps someone else has experience of this or similar?
Anyway, hope it helps, good luck and please post how you get on. a) It helps others and b) as a fellow model 90 owner I am interested in any weaknesses etc, especially as I will be relying on it as my main power unit this season
Your plan sounds good to me. I guess if it doesn't improve things you are possibly looking for a crack somewhere that is opening up once the motor has been hot for a while ( would have expected it to open a bit quicker than 20 mins to be honest though ) or maybe a joining face is a little out and a gasket is leaking when hot?
Although I haven't known of it I guess if cylinder pressure were to leak into the cooling system you would get a power loss ( hence the stopping ) and the pressure would probably over come the 'power' of the impellor and stop the water. As I say, just an idea, perhaps someone else has experience of this or similar?
Anyway, hope it helps, good luck and please post how you get on. a) It helps others and b) as a fellow model 90 owner I am interested in any weaknesses etc, especially as I will be relying on it as my main power unit this season
Hi,
bit stumped here. Are you totally sure of the order things happen? One of my 40's will run for a while, then will die off and stop. The water stops flowing just before it dies. Answer, it has a leaking head gasket. Spark plug is wet with water, not fuel. Have you checked for the same?
regards
Phil
bit stumped here. Are you totally sure of the order things happen? One of my 40's will run for a while, then will die off and stop. The water stops flowing just before it dies. Answer, it has a leaking head gasket. Spark plug is wet with water, not fuel. Have you checked for the same?
regards
Phil
Interesting thoughts. I have only had two days off in the last fortnight so am getting frustrated at not being able to test some theories with Whitworths in one hand and head in the other! I've never run it long enough in a tank for the problem to happen (I quite like my neighbours!). I think I have replaced the gasket and cleaned the water jacket in this one so CH Gasket might be a contender. It definitely loses power before cutting out but that is inevitable surely.
Click on the thumbnail for a picture of my tub on Loch Lomond with Sis in law and niece keeping the trim right! EFNRL with steel tank just visible hanging off the back. Just to cheer you up, I left the fuel can in the car that day and ran out of fuel!
Click on the thumbnail for a picture of my tub on Loch Lomond with Sis in law and niece keeping the trim right! EFNRL with steel tank just visible hanging off the back. Just to cheer you up, I left the fuel can in the car that day and ran out of fuel!
Having read through the thread I must say that the increasing likelyhood is that a head gasket problem is causing your problems.
I believe you have had the3 head off to clean out the waterways? Did you use a new gasket?
In any event, I would recommend the purchase of a new gasket, and a careful replacement. Everyone has their own ideas about gasket cement or sealant; I prefer not to use it, but many swear by it. Whatever you do make sure that all the surfaces are clean before reassembly, and I am confident this will cure your problem.
I believe you have had the3 head off to clean out the waterways? Did you use a new gasket?
In any event, I would recommend the purchase of a new gasket, and a careful replacement. Everyone has their own ideas about gasket cement or sealant; I prefer not to use it, but many swear by it. Whatever you do make sure that all the surfaces are clean before reassembly, and I am confident this will cure your problem.
Thanks
I'm going to do the lot when I can find the time:
- Remove gearbox - check impellor
- Backflush with gearbox removed
- Remove Cylinder Head
- Clean out water jacket
- Clean up head joints
- Replace head with new gasket
I have full set of new gaskets including gearbox shoe so that's not a problem. I have used Blue gasket sealant on other Seagulls and seems to work great and I am tempted to do the with this as it is sitting there anyway.
Here's hoping I don't shear the CH bolts!
Steven
I'm going to do the lot when I can find the time:
- Remove gearbox - check impellor
- Backflush with gearbox removed
- Remove Cylinder Head
- Clean out water jacket
- Clean up head joints
- Replace head with new gasket
I have full set of new gaskets including gearbox shoe so that's not a problem. I have used Blue gasket sealant on other Seagulls and seems to work great and I am tempted to do the with this as it is sitting there anyway.
Here's hoping I don't shear the CH bolts!
Steven
-
Charles uk
- Posts: 4972
- Joined: Wed Feb 27, 2008 4:38 pm
- Location: Maidenhead Berks UK
When a Seagull stops because of no water flow it normaly means it's seizing, so when your stripping it remove the cylinder & check everything in that area.
You will probably find some scoring on the exhaust side of the piston in the ring area, if your lucky, this will clean up with some fine wet & dry & there will be little or no damage to the cylinder walls.
Light scoring on the cylinder walls will clean up with gentle use of a green Scotsbright pad.
If the cylinder & piston are suitable for re-use check cylinder for cracks & rust damage & clean the water jacket with any tool that you have to hand that will remove the corrosion buildup. with your symptoms I would not be supprised if your water jacket if almost full of corrosion debris, a couple of hours work with a long screwdriver will bring it back to a very useable condition, with a new cylinder costing £150.00 ish it's well worth the effort.
Clean all the water ways with straightened out coat hanger & the air line, it is very seldom that it's the water pump impeller that causes lack of water flow.
Now reassemble with new gaskets if you have them, I allways use RTV silicon for all the gasket faces, I swear by it.
But remember it squeezes out the same amout on the inside as it does on the outside, so don't block any water ways or the transfer port.
The problem your suffering from, is often caused by lack of fresh water flushing after salt water use, which has probably killed more Seagulls than anything else, so flush in fresh water for 5 mins after every salt water outing.
Post pictures of what you find, so we all can learn from your troubles.
Good luck!
You will probably find some scoring on the exhaust side of the piston in the ring area, if your lucky, this will clean up with some fine wet & dry & there will be little or no damage to the cylinder walls.
Light scoring on the cylinder walls will clean up with gentle use of a green Scotsbright pad.
If the cylinder & piston are suitable for re-use check cylinder for cracks & rust damage & clean the water jacket with any tool that you have to hand that will remove the corrosion buildup. with your symptoms I would not be supprised if your water jacket if almost full of corrosion debris, a couple of hours work with a long screwdriver will bring it back to a very useable condition, with a new cylinder costing £150.00 ish it's well worth the effort.
Clean all the water ways with straightened out coat hanger & the air line, it is very seldom that it's the water pump impeller that causes lack of water flow.
Now reassemble with new gaskets if you have them, I allways use RTV silicon for all the gasket faces, I swear by it.
But remember it squeezes out the same amout on the inside as it does on the outside, so don't block any water ways or the transfer port.
The problem your suffering from, is often caused by lack of fresh water flushing after salt water use, which has probably killed more Seagulls than anything else, so flush in fresh water for 5 mins after every salt water outing.
Post pictures of what you find, so we all can learn from your troubles.
Good luck!
Thanks Charles
Quick update - I found a spare hour this morning and set to.
I removed the non standard brass oval tank that had replaced the leaking steel one - the brass one also seems to have a leak!! Arghhh!
Anyway - on the update. I removed the Cylinder Head with surprising ease although I think I should consider replacing the bolts preferably with stainless steel.
The water jacket was quite full with corrosion and it doesn't look like I've ever been in there. The gasket looked good as new though and no evidence of leak in the gasket to the bore.
I've attached some thumbnails for you to click away at:
First is the CH showing the rusty water jacket:
This is looking down into the bore at the exhaust port. No evidence of scoring and incredibly polished. Photo has just picked up lots of reflections so is not very good at showing how smooth the bore is:
This is the back of the Cylinder head with gasket still attached:
This is the back of the Cylinder Head with gasket removed:
This is the Cylinder Head gasket showing the side that faces the Head.
My conclusions are that there was some loose rust parts floating around that have blocked the water flow. My plan is to chip away at it, fit new gasket with rtv sealant and back flush. There is still a possibility that I have a cracked bore that is only apparent when it is very hot and that I then lose compression and create back pressure down the water feed pipe but I am ignoring that possibility for just now. The dampness on the Cylinder Head is the result of the leaky fuel tank rather than water.
Cheers
Steven
Quick update - I found a spare hour this morning and set to.
I removed the non standard brass oval tank that had replaced the leaking steel one - the brass one also seems to have a leak!! Arghhh!
Anyway - on the update. I removed the Cylinder Head with surprising ease although I think I should consider replacing the bolts preferably with stainless steel.
The water jacket was quite full with corrosion and it doesn't look like I've ever been in there. The gasket looked good as new though and no evidence of leak in the gasket to the bore.
I've attached some thumbnails for you to click away at:
First is the CH showing the rusty water jacket:
This is looking down into the bore at the exhaust port. No evidence of scoring and incredibly polished. Photo has just picked up lots of reflections so is not very good at showing how smooth the bore is:
This is the back of the Cylinder head with gasket still attached:
This is the back of the Cylinder Head with gasket removed:
This is the Cylinder Head gasket showing the side that faces the Head.
My conclusions are that there was some loose rust parts floating around that have blocked the water flow. My plan is to chip away at it, fit new gasket with rtv sealant and back flush. There is still a possibility that I have a cracked bore that is only apparent when it is very hot and that I then lose compression and create back pressure down the water feed pipe but I am ignoring that possibility for just now. The dampness on the Cylinder Head is the result of the leaky fuel tank rather than water.
Cheers
Steven
Thanks for the update and the Photos Steven, it all helps to make this site more useful.
Yes, the barrel is a tad on the rusty side and I think it a strong possibility that crud is moving around a bit ( sorry for the technical terms ) we will all keep our pinkies and whitworths crossed that you don't have a crack anywhere, as I said earlier I would have expected it to show up a little earlier than 20 mins.
Can only echo Charles' comments re flushing after use. The Loch is fresh water though isn't it? even so I would still flush after use. Once flushed I give my motors a spray up the water outlet with WD40 using a long plastic pipe on the spray head which I give a good furtle about up there to try and get the stuff to go as far round the head as I can. Can't hurt can it?
Let us know how you get on once rebuilt
Yes, the barrel is a tad on the rusty side and I think it a strong possibility that crud is moving around a bit ( sorry for the technical terms ) we will all keep our pinkies and whitworths crossed that you don't have a crack anywhere, as I said earlier I would have expected it to show up a little earlier than 20 mins.
Can only echo Charles' comments re flushing after use. The Loch is fresh water though isn't it? even so I would still flush after use. Once flushed I give my motors a spray up the water outlet with WD40 using a long plastic pipe on the spray head which I give a good furtle about up there to try and get the stuff to go as far round the head as I can. Can't hurt can it?
Let us know how you get on once rebuilt
leaking heads and gasket goo
Hello all,
bit late on this one but you have gone off down the right track.
If a motor ceases to pump after 15 or 20 minutes it is invariably one of two things, assuming you have not just motored through a slick of weed!
Leaking head gasket or worse case, hairline crack in bore.
With the head off you sometimes can see corrosion and sooty marks between waterjacket and bore, a dead givaway, but not always clearly visible.
Finding a crack in the block/bore is more difficult. If you have access to an engieering shop and crack revealing fliud great, if not, a magnifing glass and a strong light, looking for hair line black marks. If you find one then the block is U/S of course.. New blocks £140.00, plus all the rings gaskets, bolts etc....
When fitting the head gasket, British Seagull recommended, in later years, with defference to the corrosion on the surfaces, using heat proof silicone sealant. They even included phials of it in gasket sets, till they realised it would have gone off before anyone bought the gaskets!
I use it all the time and it gives good results. used sparingly it should not block internal waterways and when it has cured it can be rubbed off any external surfaces easily.
always use a new head gasket, they are only £6.50 a time still.
hope this helps,
Regards,
John
SOS
bit late on this one but you have gone off down the right track.
If a motor ceases to pump after 15 or 20 minutes it is invariably one of two things, assuming you have not just motored through a slick of weed!
Leaking head gasket or worse case, hairline crack in bore.
With the head off you sometimes can see corrosion and sooty marks between waterjacket and bore, a dead givaway, but not always clearly visible.
Finding a crack in the block/bore is more difficult. If you have access to an engieering shop and crack revealing fliud great, if not, a magnifing glass and a strong light, looking for hair line black marks. If you find one then the block is U/S of course.. New blocks £140.00, plus all the rings gaskets, bolts etc....
When fitting the head gasket, British Seagull recommended, in later years, with defference to the corrosion on the surfaces, using heat proof silicone sealant. They even included phials of it in gasket sets, till they realised it would have gone off before anyone bought the gaskets!
I use it all the time and it gives good results. used sparingly it should not block internal waterways and when it has cured it can be rubbed off any external surfaces easily.
always use a new head gasket, they are only £6.50 a time still.
hope this helps,
Regards,
John
SOS
Quick update.
All has gone well -
- I've cleared out the rusty water jacket and it was very full. Hard to tell how much was floating around freely - most of it was verrry hard to chip off!
-I took the gearbox off and back flushed to ensure all was clear. As expected, the impellor was very good.
-I took some wet and dry with a wood block to the cylinder and fitted a replacement head gasket with a light smear of silicon sealant.
- The water ways were soaked in spray 3in1 oil before fitting the head.
For extra measure I have fitted a new waterproof NGK plug cover and a new spark plug.
It started with great gusto and I ran it for 90 seconds out of the water to let the oil in the waterways really penetrate. Once cool I restarted it in a wheelie bin of water and left it running for 30mins at idle - enough revs to be pumping a good supply of water. It never skipped a beat.
I'm very happy javascript:emoticon(':D')
For added entertainment, I've included a photo of what I poured out of the gearbox in Feb last year. It has now separated into layers of water, oil and emulsion. Looks very healthy to me and probably didn't need changed.
All has gone well -
- I've cleared out the rusty water jacket and it was very full. Hard to tell how much was floating around freely - most of it was verrry hard to chip off!
-I took the gearbox off and back flushed to ensure all was clear. As expected, the impellor was very good.
-I took some wet and dry with a wood block to the cylinder and fitted a replacement head gasket with a light smear of silicon sealant.
- The water ways were soaked in spray 3in1 oil before fitting the head.
For extra measure I have fitted a new waterproof NGK plug cover and a new spark plug.
It started with great gusto and I ran it for 90 seconds out of the water to let the oil in the waterways really penetrate. Once cool I restarted it in a wheelie bin of water and left it running for 30mins at idle - enough revs to be pumping a good supply of water. It never skipped a beat.
I'm very happy javascript:emoticon(':D')
For added entertainment, I've included a photo of what I poured out of the gearbox in Feb last year. It has now separated into layers of water, oil and emulsion. Looks very healthy to me and probably didn't need changed.
