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block vs rod clearance.

Posted: Thu Jun 12, 2008 6:20 pm
by kokkolanpoika
Hi..

I found a proplem with my 2nd hand RV8 5200cc engine. It is 2nd hand when i bought it..
Seller (RPI V8) say that it has been drived couple of thousunds miles? And sound like there is little tapping noise at idle speed. (one pistons is smaller than rest of 7, i bought set of new pistons)

So now i start to build it up again. And notice that number 1 and number 3 cylinder rod bolts hit the block. Indeed they will hit the oil "pipe" witch is in the cast.

I also bought new rod bolts, and lathed top of the bolt just like used ones are.
And also block has been grinded couple of millimeters that bolts dont hit the block. But it will hit.

So what i have to do next?
Can i machine about 1,5mm away from rod bearing carrier. I mean only another (outside) side of "carrier" below the bolt "sitting place".
I cant grind anymore at the block, because i think there will be next hole, if grind still more..
Also bolt face is very small now. It can be machined about 1mm still, but then there will be clearance about 1,3mm at number 1cylinder rodbolt/block.
And number 3cylinder rodbolt/block clearance is about 0,3mm then.
So i still want to more clearance. I think that about 1,5mm clearance is absolutely safe? 0,3mm is too tight? It can be hit the block?

Hope someone understand.. :D If not i will send some picks..

Stroke is 3.543" and rod lenght is 5.85"..

Posted: Thu Jun 12, 2008 6:33 pm
by chodjinn
have you spoke to RPI about it, since you bought it from them??

Posted: Thu Jun 12, 2008 7:28 pm
by kokkolanpoika
chodjinn wrote:have you spoke to RPI about it, since you bought it from them??
No.. i bought it about 7 month ago.. :lol: So i think its too late now. :oops:

Posted: Thu Jun 12, 2008 7:34 pm
by chodjinn
Nah, under the goods and services act here in the UK you can go back, even if it was second hand. God knows why they would sell you a short engine with 1 piston a different size and catching rod bolts . . . :shock:

Posted: Fri Jun 13, 2008 10:02 pm
by Boosted LS1
After 6 months the buyer has to prove the fault and be prepared to go to court if need be which is apain in the arse. Would probably be better to shout at them a lot and see what they may do to help.

There are 2 engineering options.

1. insert a thinwall tubular sleeve into the gallery thus allowing you to grind away some aluminium from the block. A copper insert would work.

2. Divert the gallery to the outside of the block.

I wouldn't remove to much from the rods or bolts as that weakens things and upsets the balance etc.

HTH, Mike.

Posted: Sat Jun 14, 2008 7:42 pm
by kokkolanpoika
Chris say before i bought the engine that one or two pistons are worn.? So thats not a proplem. I know what i bought. (one piston is 0,03mm too small and one is 0,05mm too big..) All crank/rod cleararances are ok.
But that FUC...ING hitting bolt is proplem and subrice.. :cry:
(and also he say that this engine is not what they build, maybe V8 D or wild cat) Customer want to new engine because there is a small tapping sound at idle.) This is the reason why RPI sell this 2nd hand engine away..
But it can be small because crank cant turn hole lap..

I have to ask them some advice..

Posted: Mon Jun 16, 2008 1:42 pm
by Wotland
Hello Timo,
You should contact Real Steel. In their 90mm stroker kit they use 6.0'' rods.
I don't remember the issue number of the mag, but there was an very good article in Fast Car where they explained stroke, stroke/rod ratio, angle of rod, clearance, ... in stroker Rover V8.

Posted: Mon Jun 16, 2008 2:08 pm
by Greg55_99
Doesn't the later style timing cover make that particular oil passage redundent? I thought it was no longer used with the crank driven oil pumps.

Greg