Porous block remedies

Can anyone shed any light on the infamous porous block syndrome fixes.I've heard of two products on the market one consisting of a metal based compound the other ceramic. Also as they're added to the cooling system will it affect the radiator,matrix or other parts of cooling system.Basicly do I need to use it in the first place,I've got a 97 hse 4.6 with no engine problems.[yet]

no problem no fix needed???

gavbriggs said:

no problem no fix needed???

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Preventative maintenance

Thats like saying my big ends arent knocking yet, i wont change the oil...

Seriously though, got asked to do the head gaskets on a P38 as a homer, as it was boiling up. Told him, chances are, its going to need a new engine, due to the porous block blah blah.
Still wanted the gaskets done anyway, so had the heads skimmed and new gaskets, was just the same, still boiling up

Then he came to me with a bottle of Irontite ceramic sealer, asked if that would be any use. Was sceptical at first, but ATEOTD, it wasnt my money... Had a look round google etc, for advice on how to use it. They all said to follow the instructions TO THE LETTER. So, drained out all the anti freeze and flushed through the whole system with clean water and added it. He took it away and brought it back a couple of days later, still using a bit of water. Drained it all and left it for a couple of days to do its thing. Filled back up with 50/50 coolant and sent him on his way. Phoned me 2 weeks later to say it hadnt overheated and not loosing any water...

He bought it from P38spares.co.uk @ £30 + postage, but you can get it cheaper on Ebay, search for Irontite. We never bothered with the 3 stage things, just the single bottles...

HTH
Mike

redkevlar said:

Can anyone shed any light on the infamous porous block syndrome fixes.I've heard of two products on the market one consisting of a metal based compound the other ceramic. Also as they're added to the cooling system will it affect the radiator,matrix or other parts of cooling system.Basicly do I need to use it in the first place,I've got a 97 hse 4.6 with no engine problems.[yet]

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I don't think there has ever been a pourus block fitted to a Range Rover. This is something that developes over time and use. If proper stress relief is not carried out at the casting stage, certain areas of the block are under stress, but then weakened by machining. Constant heating and cooling as the engine is used causes cracking in these areas. So the porus block, if you want to call it that, developes over use. An engine that has been run with air locks present is much more likely to develop this problem than one that has been cared for. Many aluminium blocked V8s have suffered from this problem over the years notably the Triumph Stag engine which could boil up at will destroying it's self in the process. The Rover V8 is an old American design that was discontinued over there for that very reason. Have you ever wondered why Yank V8s mostly all have cast iron blocks. However saying that, Rover have made this engine for many years and developed it, so you would think they could have cured the problem by now.

sorry gonna have to correct you.... the rover V8 was a buick engine that was designed before they figured out how to make thinwall iron blocks it was dropped as it was more expensive to produce and less robust than a thinwall iron block, it would have been scrapped entirely if some plank from rover hadn't bought the design.

for the record a ford 302 (5.0l) V8 weighs about the same as a rover 3.5 and produces about 100bhp more but can be tuned to about 500bhp

the best i have seen from a N/A 3.5 is 260bhp (verified) where as a ford 302 will produce 300 with just a set of decent carbs

G-man said:

sorry gonna have to correct you.... the rover V8 was a buick engine that was designed before they figured out how to make thinwall iron blocks it was dropped as it was more expensive to produce and less robust than a thinwall iron block, it would have been scrapped entirely if some plank from rover hadn't bought the design.

for the record a ford 302 (5.0l) V8 weighs about the same as a rover 3.5 and produces about 100bhp more but can be tuned to about 500bhp

the best i have seen from a N/A 3.5 is 260bhp (verified) where as a ford 302 will produce 300 with just a set of decent carbs

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Is that not about what i said? "Less robust" in your statement gives a clue.

they didn't find porus block due to them not actually using it in any cars

I also read in LRO the other day (an old copy) that when rover brought the design over and developed it before production they changed the way the liners were fitted , the yanks were casing the blocks with the liners in place which made them less prone to slipping but rover didnt have the kit or the experience for that and fitted them after casting the block making them more prone to slipping especailly as thers no top hat.

Thanks rover for the years of slipped liners and wallet pain for so many owners! :doh:

G-man said:

they didn't find porus block due to them not actually using it in any cars

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As i said before there is no such thing as a porous block, only a cracked one. A porous block would leak straight away not take several years to appear.