What can go wrong next?

ribrage said:
Ummmm NO .it won't seal properly, the mating faces need to be flush to seal, as has been said prior, machine it flat to remove pitting or get a stainless fabricator to make you one ... I have a tig set inboard and odd pipes and stuff .. Where you hiding now ?
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Sicily...
 
I too have an engine with an aluminium exhaust manifold attached to a steel (mild) exhaust elbow, and have just been through the leaking exhaust into the boat saga. The end of the story is I found that the aluminium flange had cracked causing a distortion of the mating surface and needed to be welded and machined. This entailed removal of the manifold, new gaskets manufactured and the whole lot reinstalled. I spent 4 months frigging around in the deep recesses of my bilge before giving up and calling in a professional. He thinks the crack is due to the weight of an after-market steel exhaust elbow being supported by 2 bolts into the aluminium exhaust flange. Total cost - NZ$1600.
 
Couldn't sleep so I decided to take the new elbow off again an re install the old one. The seal is better but I am still getting an exhaust gas leakage between the manifold and elbow.
I will try some kind of sealant but with everything else that's wrong we are basically just going to be bobbing around where we can untill we can get in a marina in 8 weeks.
I have found some tiger sealant aboard. Does anyone know if that will work. It is used for sticking panels to cars
 
(Exhaust elbow - I've just had one made in s/s by a local metal fabricator plus a 135° elbow for £50.)
this is what I did and in S/Steel ,

but for now ,

get a sheet of aluminium as soft as possible and make your own gasket from it , not difficult .
cut the hole first , 50mm ? with a hole cutter , then drill the stud holes , then scribe the square external and cut with , whatever you have , shears ,h/d scissors ,hacksaw .

I have done this and its still on the engine after 2 years ,
good luck
 
grafozz said:
(Exhaust elbow - I've just had one made in s/s by a local metal fabricator plus a 135° elbow for £50.)
this is what I did and in S/Steel ,

but for now ,

get a sheet of aluminium as soft as possible and make your own gasket from it , not difficult .
cut the hole first , 50mm ? with a hole cutter , then drill the stud holes , then scribe the square external and cut with , whatever you have , shears ,h/d scissors ,hacksaw .

I have done this and its still on the engine after 2 years ,
good luck
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Thanks grafozz for the advice
I tried a new gasket but that was worse than putting the old one back on.
Is is the join to the heat exchanger at the top which is the problem as it appears to have corroded making it impossible to get the seal. The new gasket just forms into it leaving a slight gap for gases to escape
 
I know this won't be available unless ordered by post and so might take quite a time to arrive, but could you build back up the corroded Aluminium part by brazing and then file / machine it back to flat? It might make a permanent repair at little cost, and would allow you to use the conventional gasket.

I think it's quite plausible to do on a boat.

http://www.aluminumrepair.com/video_new.asp
 
you and Cardo could moor up against each and swap horror stories :)


Every component on board has a MTBF (Mean Time Between Failure) measured in hundreds or thousands of working or static hours. It is coincidental, and nothing to do with your dedicated maintenance routines, that a group of Failures have coincided. Proper repairs will take the next failure mode way beyond your ownership of the boat.

Seems like par for the course for many things to go wrong within a similar time frame, and some of those will be attributable to statistical misfortune, not your management.

Best of luck sorting it all out.
 
How about making an internal sleeve which could be welded to one component and slide into the other? It would only need to extend an inch or so, but would but would help prevent blow-by and allow an exhaust cement to set well between the flanges.
 
Nostrodamus said:
Now I just changed the exhaust elbow. I did enquire of mr Volvo but he was out stealing ice creams fom babies and ripping the wings off butterflies. He did leave me a message though asking for £550!!!!
I tried a Perkins dealer and he was far more helpful selling me the same part for £125.
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Count your blessings. 'Round here the Perkins and Volvo agents are one and the same!
 
{It is the join to the heat exchanger at the top which is the problem as it appears to have corroded making it impossible to get the seal. The new gasket just forms into it leaving a slight gap for gases to escape}

Araldite can often do a job to bulld up a surface.

Your heat exchanger input uses a flange and gasket?
I thought that they were mainly a push on flexable pipe held with a jubilee clip, what bad luck.
 
LadyInBed said:
{It is the join to the heat exchanger at the top which is the problem as it appears to have corroded making it impossible to get the seal. The new gasket just forms into it leaving a slight gap for gases to escape}

Araldite can often do a job to bulld up a surface.

Your heat exchanger input uses a flange and gasket?
I thought that they were mainly a push on flexable pipe held with a jubilee clip, what bad luck.
Click to expand...

It is the flange on the heat exchanger which needs to marry up with the flange on the exhaust elbow. There is a gasket between but because of corrosion on the top of the heat exchanger flange getting a seal fully is impossible. I have found some thing like a metal putty which you roll round for a couple of minutes and then push it where you need it and it sets rock solid. Seems to be working at the moment.
 
I can't vouch for the efficacy of this in your circumstances, but I have used Flue Sealant, available from plumbers merchants, to seal high temp joints. It seems to be a high temp silicone, comes in a gun-ready tube and sticks like the stickiest sticky stuff. IIRC it is rated to about 800 degrees. used for sealing flues in gas boilers. Not expensive so may be worth a try for a temp solution. Good luck...
 
Nostrodamus said:
Anyone know how hot an exhaust elbow should get?
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If the exhaust is passing into the elbow through a flange that is bolted directly to the heat exchanger, then that flange is unlikely to be much hotter than 100 Celsius, otherwise the water in the heat exchanger would boil off.

The curved section that is between the flange and the spot where the cooling water is injected into the exhaust line will be hotter.

IMO, FWIW and not having seen your set-up.
 
What can go wrong?

How about a knackered water (circulating) pump, on a VP 22, which is really a Perkins Prima, painted with expensive Volvo paint, when out on the West side of the Outer Hebrides. The pump is cleverly positioned behind the cover containing all the timing gear, pulleys, belt etc. So all the timing gear has to be stripped out, before you can even see the pump. Grrrrrr.
 
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