Hi all. Just took the 5 for a spin as weather looked ok, driving along then boom, white smoke looting out. Engine died, so pulled over, car won't turn over, still have coolent in water tank. Also no mayo in filler cap, theirs a tiny amour but hardley anything,
Any ideas? Or would you say headgasket?
Elliott
Last edited by gardner51; 22-09-2012 at 17:33.
if engine wont turn over then its unlikely to be headgasket.
Used any water at all ?
Just been recoverd to my garage,
Whipped the rocker off, no mayo... Just no valve in number 1 (turbo end)
Not happy atall!
Elliott
Car looking sorry for herself..
Had to take of front bumper to get on the truck,
got back to the garage and took rocker cover off, found i was missing a valve..
Took the head off to find....
Heres some pictures of the damage, are these standard pistons?
piston 1 (turbo end)
Piston 4
All pistons
Couple of pics of the bent valve..
So were do i go from here? am i best to buy a second hand engine? or new pistons and new had ect?
Elliott
The question is how the heck did that happen??
Do a rebuild bud you know were you stand then it's coming up to time the 5s hibernate anyway
Not sure if they are standard or aftermarket pistons, but either way they have had material machined off them ( they dish inwards ). eg low comp
As for now it happened, something has let go, either one of the collets or the spring retainer etc etc. Possibly over revving ?
i can only find one collet,
over revving im not sure, i normally change about 6.5k? unless this is to much?
this happend when i was of boost and had been for a while, following a car doing 40,
yh ws told they are low comp pistons,
problem now is i dont want to replace with standard items as car will be slower,
so do i save for forged pistons n find a good head to put on it?
Elliott
Youl probably find your turbos ingested some foreign matter, check for damage on the exhaust wheel
Yeah there low comp pistons, look like machined down standard pistons but can tell better when they are removedOriginally Posted by gardner51
If you stuck standard comp pistons in it wouldn't be slower, you'll prob find it'll have more low down torque
If you do go with standard comp pistons mate sure you get a head thats as close to factory thickness as you can (73.5mm is standard). I think Haz had a spare head for sale recently
As for how it happened do you have a performance camshaft in the engine?
Grateee. Yet more money! Looks like its going to be in storage a long time lol!
Elliott
To be honest mate shouldn't be too costly to fix that if you replaced the head, pistons and made sure liners ok.
Weekends work too
Cheers marky, for that info, ill prob go forged pistons whilst engine is apart?
Yep have a 280 or 285 cam,
If I go low comp again or forged. Does head thickness still matter? Is thicker the better?
Ellz
Ellz if you cant afford to go low comp its fine, standard bottom ends have been known to go 25/30 psi - and your only wanting 20-22 so if you need to go standard compression itl be fine.
I know someone who had a good head for sale which i was thinking of buying as a spare, its thick (close to standard, so hasnt been skimmed much) and i think its had some port work done aswell - perfect!
Are you going to replace just the 2 damaged pistons or all 4?
If your not pushing the engine hard theres no real need to go forged pistons, as James says standards are fine and hold up well with a fair bit of boost
The thickness of the head is more an issue when the comp is higher but it will also determine the final comp ratio wether you go standard or low comp pistons, my advice try find as thick as you can and don't go thinner than 73mm
As you got a 285 cam do you have the valve springs to match?
Yh James I see what your saying. but as its apart and In no rush to put back together may go down that route,
Yh send me a pm about the head please,
Ellz
like mark says definatley need a 73mm thick head minimum!
And yes mark as far as he was told it had a 285 cam and piper springs - we can now check this though with it all coming out
If got the springs won't be valve bounce then, maybe just faulty retainer or top hat which finally let go
Yes mark had everything needed I think, had bigger valves to apparently?
Cheers for the info
Elliott
Springs look like piper to me. OE ones have red colouring on them. These look plain to me ?
Yh they are plain I think buddy,
Ellz
bad luck mate.
i have 3 of these piston in the garage which came out my old dead engine so if you want to replace your fubared one i can send one down to you if you cover postage. saves buying a new set
Exactly the same thing happened to my old c1j the Collet gave way and I could only find enough bits of Collet to add up to one half, the damage to my pistons wasn't as bad as yours so all I did was use a grinding Stone and flattened off the mark the valve had left.
I also had the cylinder head repaired it needed a new valve guide and a new valve seat and a light skim.
as Kris says once the lump was bolted back toghether the turbo let go after about 50 or so miles, you might be lucky but I doubt it.
Tubbyg see pm
I don't think ill be able to get my head repaird, the way its been pushed in its smashed it, if I can remove the valve ill get clearer pictures up,
I'll check turbo out in the week as busy tomorow
Elliott
My pal repairs heads and blocks with fist size holes through them. And the repairs are stronger than the original.
It's just about cost and if it's cheaper to get a replacement head.
You can use a skimmed head if you use low comp piston tops. I did, with the resulting compression ratio of 8:1, slightly higher that standard, which is what I intended. I wanted the 'dishes' in the piston tops as the idea was that they increase the swirl, therefore increase the mix therefore reduce the detonation.
And while you're having that done, you can get the pistons and con rods balanced.
So is making the compreshion ratio higher a better thing?
Elliott
It can be. That engine in Phil red 5 that just made 260bhp at Scoff RR is a somewhat high compression, based on and maybe furthering work developed previously on mine and others by Big Jim Racing.
I think for road use they might be better as there's a bit more 'off boost' power. A pal had a what was maybe a 9.5:1, not sure as it was skimmed a couple more times after originally measured with a burette. But I drove that car and it was so smooth, like a naturally aspirated engine. But still made about 240bhp and 230ft lbs and at only about 18psi or so using a VNT and through the carb rather than EFI. Due to is smooth torque delivery, in the wet it would make a couple or few car lengths over mine while I balanced the pedals to find traction as the boost whacked in and span the wheels. Phils engine would be the EFI version of that engine.
I think it's fair to say that lower compression equates to less off boost drive and perhaps more lag.
I twice had the valve thing like you just did. I was using original springs, first on the original engine and then with a Piper 270 cam. With the second one, bits of shattered valve guide bent over the turbine vanes as they went past and into the exhaust. Liners were scored as well as piston tops and head gouged. Bits of collet damaged the sprockets and maybe the chain and scored the metal part of the crankshaft oil seal.
After that I used new springs. CTM, in Dagenham, specially lowered the spring seats so as to fit the custom specification longer firmer springs (they measured the required 'weight' and length using a machine they have for that purpose) so as to more easily accommodate the high lift of a Piper 285. Big Jim made some special spring caps.
I see, well I deffantly don't want any more lag then I have already, 4k as it was is enough lol,
Elliott x
Today I removed a piston to see if theirs any other damage,
It looks like abit of the piston or part of the head has scored down the liner, its not deep and can barley feel it with a fingernail,
Will this be ok?
Elliott
i got told if you cant feel it with your finger nail it will be ok. Im sure someone with some better knowledge will be along with some better info
But I can just about feel it.
God sake!
Ellz
mechanic nails, or freshly manicured?
lol!mechanic nails, or freshly manicured?
Mechanic nails...mechanic nails, or freshly manicured?
Who you trying to kid ellz, wouldnt surprise me if you get a manicure same time you go for your sunbeds!
Lol...my tan is real...
So what we saying. Should be fine yh?
its not much more effort to find a good used liner than live with the doubt of it not being ok.
im sure mike will have a spare... imo thats what id do. do it once do it right and all that.....
Can I change just a single one? Are they easy to change? Atm their all held down, do I just undo my DIY bolts/washers and pull it out?
Elliott
yeah keep bolts holding the others down, pull liner out, clean the area where the liner seals, id put a smear of silicone on when fitting new liner with new seal then same build back upbe carefull not to damage the other seals when cleaning the block.
Next time I go round to my mums ill check for a spare liner for you. I'm sure I've got 3 good ones in there. Yours for free if I've still got them.
Ross
Posting Permissions
Reply With Quote
