gb86
New member
I (foolishly...?) bought a '98 sei sporting a few weeks ago as a non runner, with a view to get it back on the road. The guy i had bought it from had only just bought it himself, drove it 60 miles and then it stopped working. He didnt know much about the thing but it had evidently overheated and subsequently died.
Got it home and put a compression tester over the plug holes and its well under normal compression. look at the oil and its all emulsified. I notice it also has a brand new radiator. So i'm thinking; radiator must have leaked, causing it to over heat and slightly blow HG. Previous previous owner gets rad replaced but due to the slightly blown HG it still has issues so he flogs it. Owner before me buys it, drives it home and properly cooks the engine, completely destroying the HG and maybe warping the head. Then buy it.....
It's ok, i think to myself, cos i have a spare head at home, taken from a cinq that didnt overheat, and i'll replace the HG and the head to cover myself. I do this, and, after a bit of fiddling it fires up (it has a bike exhaust on the back and it sounds good). So far so good. So i replace oil with some wilko budget oil to flush, and fill the coolant reservoir with water. Now i start getting issues...
I let it run for a few minutes and the temperature warning light comes on, so i turn the engine off. I dont actually think the thing was running long enough to overheat unless there are airlocks in the cooling system, and also wonder why my rad fan didnt kick in. So i paperclip the fan switch and the fan works. I have a brand new spare fan switch in the garage so i screw that into the brand new rad. looks nice. I run the engine again and it sounds like everything is going ok, radiator begins to heat up. I watch tentatively at the dash and then the damned overheating light comes on again. I turn the engine off. Why aren't sei's fitted with a temp guage?!!? I can't tell what temp the engine is at before its too late so i have no idea i things are doing what they should be doing. At this point, i decide that when i finish this job, i keep my cinq and sell this sei! So as the engine is warm i drain the flushing oil and put in another load of flushing oil for good measure. I also pull the pipe off the bottom of the rad and drain the cooling system, pour a few bottles of water in the top to clear it out a bit and fill and bleed. I have it with the front end up at this point to properly bleed the system at both bleed points.
However, after all this is havent managed to sort out the issue. When i run the engine, the heater fans dont work properly, so there must be an air lock or blockage in the coolant system?!?
Interestingly, when the overheating light comes on, at first it glows very faintly and slowly gets brighter... not sure if that's relevant both worth a mention.
Finally, and perhaps most alarmingly, after the engine has run and i turn it off, when i remove the coolant reservoir cap it pushes out water. I swapped the cap with the one on my cinq but the same thing happens. Does this all point to head gasket?!!? cylinder pressure escaping into water jacket and increasing pressure in coolant system thus the spray when i take off the cap and the intermittent heater blowers? It seems reasonable but then again i have just replaced the HG and head and loathe to think i need to do it again. I have done HGs on cinqs and old pandas a few times and not had trouble in the past. I DIDNT replace the stretch bolts but have not done so in the past and its all been fine. Could it be anything other than the HG?
Your thoughts and advice are welcomed before i give in an buy another gasket set on ebay...
Got it home and put a compression tester over the plug holes and its well under normal compression. look at the oil and its all emulsified. I notice it also has a brand new radiator. So i'm thinking; radiator must have leaked, causing it to over heat and slightly blow HG. Previous previous owner gets rad replaced but due to the slightly blown HG it still has issues so he flogs it. Owner before me buys it, drives it home and properly cooks the engine, completely destroying the HG and maybe warping the head. Then buy it.....
It's ok, i think to myself, cos i have a spare head at home, taken from a cinq that didnt overheat, and i'll replace the HG and the head to cover myself. I do this, and, after a bit of fiddling it fires up (it has a bike exhaust on the back and it sounds good). So far so good. So i replace oil with some wilko budget oil to flush, and fill the coolant reservoir with water. Now i start getting issues...
I let it run for a few minutes and the temperature warning light comes on, so i turn the engine off. I dont actually think the thing was running long enough to overheat unless there are airlocks in the cooling system, and also wonder why my rad fan didnt kick in. So i paperclip the fan switch and the fan works. I have a brand new spare fan switch in the garage so i screw that into the brand new rad. looks nice. I run the engine again and it sounds like everything is going ok, radiator begins to heat up. I watch tentatively at the dash and then the damned overheating light comes on again. I turn the engine off. Why aren't sei's fitted with a temp guage?!!? I can't tell what temp the engine is at before its too late so i have no idea i things are doing what they should be doing. At this point, i decide that when i finish this job, i keep my cinq and sell this sei! So as the engine is warm i drain the flushing oil and put in another load of flushing oil for good measure. I also pull the pipe off the bottom of the rad and drain the cooling system, pour a few bottles of water in the top to clear it out a bit and fill and bleed. I have it with the front end up at this point to properly bleed the system at both bleed points.
However, after all this is havent managed to sort out the issue. When i run the engine, the heater fans dont work properly, so there must be an air lock or blockage in the coolant system?!?
Interestingly, when the overheating light comes on, at first it glows very faintly and slowly gets brighter... not sure if that's relevant both worth a mention.
Finally, and perhaps most alarmingly, after the engine has run and i turn it off, when i remove the coolant reservoir cap it pushes out water. I swapped the cap with the one on my cinq but the same thing happens. Does this all point to head gasket?!!? cylinder pressure escaping into water jacket and increasing pressure in coolant system thus the spray when i take off the cap and the intermittent heater blowers? It seems reasonable but then again i have just replaced the HG and head and loathe to think i need to do it again. I have done HGs on cinqs and old pandas a few times and not had trouble in the past. I DIDNT replace the stretch bolts but have not done so in the past and its all been fine. Could it be anything other than the HG?
Your thoughts and advice are welcomed before i give in an buy another gasket set on ebay...
