RichardS
N/A
Not so much a crack in the valve seat ...... more like a bloody great hole in the exhaust port.
Doesn't look good.
Richard
found this on another forum , first thing I thought
" It is possible to get the head bored out into the exhaust port and then a sleeve inserted. The last person i told this method got a machine shop to do the work for 150 pounds. the sleeve was steel and they used liquid nitrogen to cool it before inserting it."
Damni really hope that if I buy. New one it cures my problems...
Could this hole be the cause of underpowered engine which runs for 1-5 min then cuts out
Any links where to buy a cheap head?
I haven't checked the condition of my injector and pre combustion?
Cheers for the input everyone!
Any links where to buy a cheap head?
Do you have anyone who could bring one in from the US for you? If so, find a Yanmar dealer covering their state and order it there. I have just checked, and when I bought one it cost $505 (£310), as opposed to £451 in the UK. It came across in hold luggage with no problems or questions and was in any case under the duty free limit for gifts.
The complete list for that order was
728170-11700 complete cylinder head $505.00
105582-49200 raw water thermostat $26.75
128171-01911 cylinder head gasket $37.25
128275-91340 temperature alarm switch $21.50
128170-13201 exhaust elbow gasket $5.25
128170-11310 rocker cover gasket $4.50
104211-49160 thermostat / anode gasket (2) $1.50 each
27210-200200 zinc anode $3.90
to which was added
105311-11420 Front Chamber $113.50
128275-11490 Insulator $7.00
128275-11500 Cover $4.00
Funny, I've just done a similar thing.
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I assume that's the type of sleeve repair mentioned in post #20? It looks sound. Perhaps you could advise the OP where you had this done?
Richard
Yes,
The same repair as in post 20. I have a Couple of machines and did it myself. I've done a couple before but this was the worst one for corrosion. The sleeve is made from stainless, but unfortunately I couldn't achieve a press fit because most of the original metal has been removed, so my first idea was to press it onto soft copper wire to form a seal.
In the end I used a lead washer, the type electricians use when joining conduit to boxes, under the bottom face nothing under the top-hat portion and I left the sleeve 0.5mm proud of the casting face, so that when the exhaust is bolted on, it will compress it into the lead washer.
There's nothing there that you shouldn't be able to clean / scrape and refurbish. The blocked seawater inlet into the elbow would have tended to cause overheating but I doubt that would have stopped the engine in just a few minutes. The exhaust flow is somewhat restricted which would have affected power output but it's not serious enough to have stopped the engine.
I suspect that you have a problem with fuel flow caused by air leakage into the fuel system or a blocked fuel filter or air filter or tank vent. It might be difficult to pin this down until you clean and re-assemble the engine and get it running again.
Richard
Thanks all. A new cylinder head with valves delivered is £520.
What to do... I'm concerned that I replace head and it doesn't work because the engines sat for 2 years wil raw water able to penetrate the cylinder head possibly getting into the engine block/oil and corroding inside? Any thoughts please?
I'm beginning to give up on this boat due to all the problems I'm having![]()
...I'm beginning to give up on this boat due to all the problems I'm having![]()