I thought that my cooling and missfire issues were due to a blown head gasket, although things never seem to work out as planned.

Notice the crack inbetween cylinders one and two ?



Why and how could have this happened ? It's not a big power car. I had the short motor assembled by my engine builder 6000kms ago.

I beleive the previous owner had new liners fitted by reputable engineering company not long before he sold it to me as well..

I guess i am looking for another block ?
No matter how good I have been this year I don't think santa is going to put a new block under the tree for me!

Thanks,
Damion.

 

Forgive me if am wrong here....but...it looks like the block has been linered because the block is cracked - the cracks dont appear to reach the two cylinders so shouldnt affect the running of the engine!??

 

I agree with Lee, liners dont appear cracked so crack should'nt affect it. Was there any visual damage to the headgasket? Also, was the misfire constant when running the car, even on idle? or just a boost misfire?

 

agreed with the above comments

 

Thanks for the replies, i have found another crack similar to the above between 3 and 4 now too.

The missfire was only up top in the rev range, so it may not be related... but the cooling issues would be due to this I would atleast think ? as the cooling system is under pressure.. im guessing under load the combustion pressures would drive the coolant away from entering the cylinder..

The car was starting to miss and carry on badly when i was starting it etc which i thought may have been coolant in the cylinder

On the gasket there was evidence of some damage where the first crack was and also around one of the bores on the gasket

 

dont suppose you checked the compression on each bore before you removed the head? it is a possibility that the overheating issue was nothing to do with the problem areas you are finding now, but it may have caused them (thats head gasket damage and overheating, not cracks). i dont think you need to worry about the cracks on the block, as long as the liners are ok. The overheating could have warped the head, thus creating a leak path for the coolant to a chambre, or something along those lines. Also, i dont think your high rev missfire would be related to this, but if it is missing on idle, sounds like its running on 3 cylinders or something, this would probably be the cause.

 

is it just me or have the valves been hitting the tops of those pistons? they dont look like machined valve seats.....

 

have you cleaned that piston ? it looks too clean one is black and one is fairly clean. id say defo been water getting in there somehow.

 

Yeah i may have semi cleaned that piston as i was wiping down around that area on the block with petrol.

I bought a cheap compression tester and tested it cold at 110, 120, 120, 120.. although when i got the engine warm the bloody end bit broke. I had a c02 test done on the cooling system and it showed that combustion was definately getting into the cooling system.

The car would miss (like running on three cylinders etc) when i start it up and it was gradually getting worse and worse.. and also when i reved it flat out and backed off it and then tried to get back on the throttle flat out it would miss as well.

And those are actually cuts into the pistons.. i paid for them to get done, they just didnt do a very good job !

P.S. where do you guys recomend I should looking for a 200 block ? You can buy them new now as well ?? Freight is going to be a killer to Aus !

Cheers.

 

compression results seem ok i thing, strange. Maybe the problem only exists once the engine has warmed up a bit. I personally would'nt write that block off just yet mate! Can you test the flatness of the head? it could be this giving you the sealing issues. A new 200 block aint cheap, you probably be best trying to find someone breaking one who has had a rebuild recently, or it will cost mega bucks!

 

Cheers, yeah I figured a new block wouldnt be cheap.. I will just have to have a look around at what else is going.

As far as I understand the crack is still through the water jacket ? so if I were to reuse it I would still have to try and get it repaired ?.. which will probably require the liners to come out etc ?

I will see what i can do about checking the flatness of the head, although I think it should still be fine as I never let it get too hot as I was paranoid about it.

Thanks.

 

Just find yourself a late good pinto 2 litre block locally, unless you want big power it will be fine, plenty of them in Aus

 

i would send the head in and have it all cheaked over i had my head presher tested flashed over new gides recut seats valves regrind the lot £240 its nit a lot to no that its spot on befor its bolted back on to the car

 

nearly all cossie specially if standard will have some sort of valve marks on the piston

 

Mine too...

 

Why is that?

 

not sure tbh think they must clip at high rpm

 

sticking valve(s) ?

 

Valves hitting pistons ain't good, my cossie's done 150k with out any contact, a slightly bent vale is bin fodder.

 

Has anyone had anything to do with these guys ? www.rallyespares.co.uk/pages/newparts.html

New Cosworth 200 Block, £495.00

as woodford garage have new blocks for 2k, so why the massive variance in price ?

 

if you call Paul at North Yorks RS Spares - http://www.cosworthrsspares.co.uk/ (england 01751 477766) he will sort you out with whatever you need!

is there any reason why you want a 200 block? - what power are you running?

 

typically people not timing up correctly and people bouncing the motor off the rev limiter all the time

although my cossie never had any piston to valve contact

 

Cheers LHD220Turbo, I might try and get in touch with them when I have sorted out what I am doing.

The car was making 285rwhp last time I had it on the rollers, I guess I want a 200 block for the peice of mind and I dare say I will get hp greedy eventually.

 

no worries

do yourself a favour though mate, just get a decent 205 block and save yourself the extra $$$

anyhow; i'm sure you can get a 205 block over in OZ fairly easily; they are quite common place

a 200 block is overkill for that power

a 205 block, in my opinion, is good for 500hp (at the fly).

 

i second that mate you only need a 205 block

 

Alrighty thanks fellas, yeah tracking down a 205 block here is probably possible and I guess would save me who knows how much in freight ! My head was close to $500 to ship over so i would hate to think would a block would cost !

I guess a bored block will be weaker ?

 

ideally if you can find an un-bored block then even better, it just gives you more rebuilds

a rebored block wont be any weaker as such, as long as its isnt over bored

have you tried any of the rs owners clubs in OZ?

Ford RS Owners Club (Australia)
P.O. Box S309,
Home Bush South
NSW 2140,
Australia
Stephen Roser 00 61 2 9676-6818

Email: rsoc@hotmail.com
Web:

Or

http://www.rsocvic.com/

 

Thanks for all the help LHD220Turbo,

I have got a couple people looking out for me, so hopefully it wont be hard to find something.

Will keep yaz posted/

 

No worries; no trouble at all

 

Hi all,

I finally tracked down another 205 block here in aus, it was supposed to be on a standard bore, although upon measuring it measures up at 20 thou over.

So I am up for another set of pistons. What do people recomend I use ? I figure it would be better to splash out a little bit more for forgies over another set of Mahles ? But what is the best option cost vs quality wise ? and where should I be looking to buy from ?

Is it fine to bore it out to 40 thou ? Will it weaken the block much ? I figure I fresh bore for fresh pistons would be a smart move.

Thanks.

 

over revving the engine passing the limiter.. the valves cant close fast enough before the piston has moved away, hi revving engines use double valve springs to make sure the valves are closed and out the way.

 

yup theres no reason you cant use a pinto 205 block.. only difference is the waterways are slightly different

 

mahles are forged as standard my friend and are good for 500bhp is standard format

the 205 blocks are on there limit at .5 bored, so i would either go for that or maybe look at getting the block lined

best person to source them (Pistons, bearing, shells etc) is Matt Lewis motosport in England, if you cant source them in OZ

Matt Lewis Motorsport - Cosworth & RS Parts Specialist-Worldwide Mailorder.
Unit 4 & 5 Chasewood Park Business Centre
Hednesford Road, Heath Hayes
Cannock, Staffs, WS12 3XR - 01543 448848
http://stores.shop.ebay.co.uk/Matt-L...rsport?afsrc=1

Cheers
Matt

 

Cheers Matt,

I was under the impression that the Mahle's were cast ? Burtons list them as cast pistons ?
My block is already bored 20thou (0.5mm) over and if I were to buy new pistons I would be looking to bore it again to have a fresh bore for the new pistons.. damn.

Not keen on liners as that is they had something to do with the last block perishing I'm sure.

I have bought stuff from Matt Lewis Motorsport before, so when I figure out what I am doing I may do so again.

Thanks,

Damion.

 

Sorry Damion, only just seen this reply

you can bore safely from standard (which i think was 90.8 from memory) to +1mm, this is common place and not a problem.

if the block/ bores are in good condition you can go as much as 93mm but this might question the strength etc

Matt