more hot water woes

[Smelly]

Well the water's cooling again so I think the calorifier circuit is airlocked again, second time in a fortnight...

 

I can nip to.screwfix and get an air valve but alleviating the symptoms is not finding a cure.

 

I suspect a very slight leak somewhere; possibly only on cooling and not emitting any coolant, just sucking air in which will be a right barsteward to track down.

 

When I took the cap.off to check the coolant there was suction holding the cap down (engine was still quite warm). A clue? Need I worry about my head gasket of 6000 hours virtue? If so will a pressure test tell me much?

 

It's effectively a sealed system so I'd expect some suction as it cools if it does indeed blow at 1 bar.

 

Other than renewing connections is there anything I can do?

[MoominPapa]

When I took the cap.off to check the coolant there was suction holding the cap down (engine was still quite warm). A clue? Need I worry about my head gasket of 6000 hours virtue? If so will a pressure test tell me much?

Does your pressure cap have a little valve in the middle to let stuff back into the cooling system as it cools? If so, is it jammed closed?

 

MP.

[Smelly]

Does your pressure cap have a little valve in the middle to let stuff back into the cooling system as it cools? If so, is it jammed closed?

 

MP.

 

I hope so... Will have a fiddle tonight.

[Chalky]

I had a strange loss of water on an MGB engine and a slight vacuum. Turned out to be head gasket. There is a kit that garages use that can test for combustion products in the coolant - easier than a strip down.

Could also be worth changing the radiator cap.

 

Have you re-filled the cooling system recently? There tends to be a fair amount of air disolved in the water and this can sometimes take a while to work its way through.

[Smelly]

I had a strange loss of water on an MGB engine and a slight vacuum. Turned out to be head gasket. There is a kit that garages use that can test for combustion products in the coolant - easier than a strip down.

Could also be worth changing the radiator cap.

 

Have you re-filled the cooling system recently? There tends to be a fair amount of air disolved in the water and this can sometimes take a while to work its way through.

 

Are radiator caps standard?

 

I was thinking maybe Baldock had posted a link to similar. It may well be in the offing.

 

I topped up with a couple of litres when I bled it last week, nowt more though...

[mikevye]

Fraid to say classic head gasket symptoms. Head gasket leakage causes excessive pressure forces water out of system usually via the rad cap remaining coolant contracts when the engine has shut down causing a vacuum. If the leak is external including the calorifier it is highly unlikely that a vacuum would result as a consequence.

[RLWP]

Well the water's cooling again so I think the calorifier circuit is airlocked again, second time in a fortnight...

 

I can nip to.screwfix and get an air valve but alleviating the symptoms is not finding a cure.

 

I suspect a very slight leak somewhere; possibly only on cooling and not emitting any coolant, just sucking air in which will be a right barsteward to track down.

 

When I took the cap.off to check the coolant there was suction holding the cap down (engine was still quite warm). A clue? Need I worry about my head gasket of 6000 hours virtue? If so will a pressure test tell me much?

 

It's effectively a sealed system so I'd expect some suction as it cools if it does indeed blow at 1 bar.

 

Other than renewing connections is there anything I can do?

 

What engine have you got Smelly?

 

Richard

[Smelly]

What engine have you got Smelly?

 

Richard

 

Isuzu 35 I think it's a 4LB1.

 

Fraid to say classic head gasket symptoms. Head gasket leakage causes excessive pressure forces water out of system usually via the rad cap remaining coolant contracts when the engine has shut down causing a vacuum. If the leak is external including the calorifier it is highly unlikely that a vacuum would result as a consequence.

 

It doesn't seem to be losing much coolant though...

 

I'm seriously considering that head gasket kit. and a new generator

[Chris-B]

PM sent Smelly

[luda]

Hi

I have a twin coil califier which is fitted horizontaly on the counter of my boat, I have drained the calorfier down is it safe to

run the engine, opinions please. Thanks

[JGMarine]

The isuzu 35 does not have any head gasket issues.

Sounds to me like a coolant leak which will affect the calorifier circuit first when the level gets low.

A cooling system pressure test should reveal any leaks. That would be my first test before any thing else.

[RLWP]

What engine have you got Smelly?

 

Richard

 

 

Isuzu 35 I think it's a 4LB1.

<snip>

 

 

The isuzu 35 does not have any head gasket issues.

<snip>

 

That's the sort of information I was hoping to flush out. Thanks JGMarine

 

Richard

[alan_fincher]

Hi

I have a twin coil califier which is fitted horizontaly on the counter of my boat, I have drained the calorfier down is it safe to

run the engine, opinions please. Thanks

 

Yes, absolutely fine.

 

I assume you mean it's in the counter of the boat, rather than on it!

[Smelly]

PM sent Smelly

 

Cheers fella

 

The isuzu 35 does not have any head gasket issues.

Sounds to me like a coolant leak which will affect the calorifier circuit first when the level gets low.

A cooling system pressure test should reveal any leaks. That would be my first test before any thing else.

 

You'll note that was my initial thought. OS there a kit? I'll.shuftie.screwfix later but suggestions are welcome.

[luda]

Thanks for that alan I had read somewhere it could cause problems with the coils

 

cheers

[Smelly]

and I got home and looked at the filler cap. In valve absentia and having lost a header tank full of coolant in 10 days my suspicions are high... The cabin bilge is dry and thinking about it on the way here there was an annoying hissy noise from the engine 'ole I was meaning to check out..... Bugger!

 

Mr Balders, by whichever way I need to ask whether the informed amateur can do the deed, whether all the gaskets need doing at once, and proper prices...

 

I have ordered the block kit which will be here in 48 hours so will wait until then however I'm pretty convinced i'll find combustibles in the coolant...........

 

The engine is our only source of elecrickery... Will anyone shout "NOOOOOOOO" to running it for charge or will we get away with it?

 

Budding boat mechanics around Alvechurch... Applications are welcome!

 

 

Happy Yule!

[Smelly]

and I got home and looked at the filler cap. In valve absentia and having lost a header tank full of coolant in 10 days my suspicions are high... The cabin bilge is dry and thinking about it on the way here there was an annoying hissy noise from the engine 'ole I was meaning to check out..... Bugger!

 

Mr Balders, by whichever way I need to ask whether the informed amateur can do the deed, whether all the gaskets need doing at once, and proper prices...

 

I have ordered the block kit which will be here in 48 hours so will wait until then however I'm pretty convinced i'll find combustibles in the coolant...........

 

The engine is our only source of elecrickery... Will anyone shout "NOOOOOOOO" to running it for charge or will we get away with it?

 

Budding boat mechanics around Alvechurch... Applications are welcome!

 

 

Happy Yule!

 

Intriguingly, the oil looks ok, maybe a wee bit milky but viewed under the pure white of my Petzl that's not a huge surprise.

 

There's still the annoying hissy noise, still the vacuum when it's cool and still losing coolant; I've been chatting to a mate tonight and he suggested,a s is the case, that the exhaust might look steamy...

 

Thoughts, if anyone fancies proselytising until the block kit arrives that is...

[Alan Saunders]

Intriguingly, the oil looks ok, maybe a wee bit milky but viewed under the pure white of my Petzl that's not a huge surprise.

 

There's still the annoying hissy noise, still the vacuum when it's cool and still losing coolant; I've been chatting to a mate tonight and he suggested,a s is the case, that the exhaust might look steamy...

 

Thoughts, if anyone fancies proselytising until the block kit arrives that is...

Bars Leaks, Radweld, K-Seal etc? They often work. No doubt, others will say "don't use this stuff".

 

The 'Crackle Test' can detect 500 ppm water in oil. e.g. instruction at machinerylubrication.com.

The 'Oil blotter spot test' can be useful for other conditions. You just need a non-glossy card, e.g. a business card - support it on a cup. Or you can buy Oil-Spy - who conveniently provide instructions on their website.

 

Alan

[Smelly]

Well the crackle test was weakly positive and although I can't get to the dropper test instruction presently I've 3 drops of oil on a sheet of 80gsm paper... It's black, there are some jagged edges and some smooth edges so again, well equivocal.

 

I'm almost wanting it to have failed now, the workshop manual's arrived and it looks a relatively easy job... No special tools, I'm sorely tempted...

[Smelly]

The isuzu 35 does not have any head gasket issues.

 

 

This one certainly does, and chatting about changing it with 2 hire fleets that use them they are rather familiar with the process of changing them...

 

Little engine might only be 5 years old but it's done 6000 hrs, a lot charging the batteries,.I think, now I've rebalanced the hot water so the fire's looking after it I'll be looking at either fixing or replacing the genny and buying a decent battery charger.

[JGMarine]

This one certainly does, and chatting about changing it with 2 hire fleets that use them they are rather familiar with the process of changing them...

 

Little engine might only be 5 years old but it's done 6000 hrs, a lot charging the batteries,.I think, now I've rebalanced the hot water so the fire's looking after it I'll be looking at either fixing or replacing the genny and buying a decent battery charger.

 

Having been a recognised isuzu engineer since they were first introduced i have never come across or heard of the 35 having a head gasket issue.

Now the isuzu 55 (LE1) had serious issues hence the change to the LE2 engine.

 

Be intersested if the head gasket is the problem.

 

If you are going to change it remember to use new head bolts as they are a stretch bolt and can only be used once.

[Smelly]

i'll resile the "certainly" having found a sneaky leak... I'm still worried about those green tests though.

[Smelly]

bump...

 

once the coolant level gets low the calorifier circuit is the first to suffer.

 

I didn't want to gainsay this but there was quite a lot of coolant in the header the second time.. I know from a previous leak how low the header needs to get and it wasn't that low.

 

It's airlocked again; that's 4 times and one, very titchy, taking a good few days to pool enough to reveal the puddle under the cal', leak discovered.

 

I'll have another dig tomorrow but methinks the head will be coming off...

 

The lads at Anglowelsh told me that on the 35s they often go slightly, with no visible damage to the head. Anyone care to offer their opinion?

 

It's interesting that as soon as the temp rises again we start having problems...