So, The story continues. After finding the 26 down on compression on two cylinders (what a surprise!) I got the engine rebuilt and went forged - Wossner pistons/rods, uprated Valves/springs, new hybrid turbo, decat. Carried out the run in process of a thousand miles, had it mapped to new 630 injectors and I was a happy bunny - the car is stonkingly fast. I've always been a bit anal with my warm up routine, I always make sure to get the all fluids upto temp before giving it the beans. Have done about 1000 miles since its mapped and finished. I went out for a bit of driving and started to notice some blue smoke when lifting off throttle... worse when going downhill it seams. I had a friend following me at the time - we spoke on the phone while I adjusted the throttle - no smoke under partial/constant throttle. It's only when I lift off do I get a plume of smoke. I haven't driven the car since. Has anyone had anything similar? PCV system? Turbo oil seal? valve stem seals? I'm racking my brain to figure it out.
It was built in the summer, and I picked it up complete after mapping July 1st. It’s from a very well respected/recommended company (esp on these forums. I’m not saying who it is.) - I'm struggling to get contact from them at the moment. But I know they’re very busy. Getting a little frustrated. I don’t want to compromise my warranty by doing something to the car, and I’m not able to drive the car it if it’s puffing our blue smoke. So I’m just having to wait until I get a response. I was just wondering if anyone else has had similar issues. If the PCV is stuck open it would draw oil from the engine into the intake, right?
Hi Bob To put it plainly you hybrid turbo is fucked. A standard turbo has plain bearing, if it over spins it will kill the bearing and the thrust seal. I've had 3 hybrid turbo's, all of them failed, best was about 2k miles worst was just under 700. This is what happened to the best hybrid turbo i had https://flic.kr/p/2jqZ6Mo Do you know how much you were charged for the turbo ???, there are some good ones around but most are using cheap Chinese parts. You would need to spend close to £2k for a possibly good hybrid, this is now why i use the 6758 twin Scroll turbo, it's rated at 500hp standard, my R26 made 436, but was dropped back to 403hp, we thing the head has been skimmed in the past and put the compression ratio up, that why it didn't get to an expected 450 ish. To be honest it doesn't really need any more power than that for a MK2. https://flic.kr/p/2pcxs3g
Grrrrreat…. Oh joy. thanks for your response Ian - sorry you’ve had so many issues. I’ll have to get it trailered/towed back to the builder…
Ohhh i can't wait to hear what he will say about that, i think i will know and the last word will be "off" i'm sure. But i really hope i'm wrong for your sake
I appreciate this thread is a little old but my complaints are similar. I've a proper Frankenstein engine. 250 bottom end completely standard Clio 197/200 head Megane 250 Intake manifold Megane 250 turbo - freshly rebuilt Clio 197 head gasket The 197 head was pressure tested and all valves replaced, seals and anything else necessary was done prior to fitting on the engine. Bottom end, as I understand it, the ring gaps were checked and there was no evidence of bore scoring so left alone. Since the car returned, it's using alot of oil and quite smokey, initially on overrun but it progressed to being smokey from start up. Very little mileage done, just some sub 3k rpm driving including an extended session in case the oil was in the exhaust system from the initial turbo failure. Turbo was my initial thought, on the intake side it's completely clean. Mechanic doesn't think it's the turbo as it's be a first for the rebuilder to have for wrong... What can I check, being a mix of engines I've a mismash of vacuum lines etc... could there be incorrect plumbing causing issues? The breather from the head to the intake, I have plumbed into what is a sensor of some description on the 250 intake. The mapper has suggested that we run the PCV to a catch can instead of this and block this sensor. Could it be as simple as a failed PCV? Car is with my mechanic and im not getting much updates. . Could the Clio 197.head gasket be causing issues?
I'm based in Ireland. Head rebuilt by a well regarded engine machine shop specialising in heads etc.. Bolted together by my mechanic that is an ex- Renault Master Tech and a specialist RS Renault guy
Smoke on the over run normally means valve stem seals/valve guides and or both or it can also be piston rings. How quick is the oil going dark ??? If it's going dark quickly it'll be the piston rings. Another possibility Have you used the Clio breather plate ????
I don't know which breather plate has been used. Would have had both options but I expect it's the Clio one that has been used as it would have been with that head.. What would the impact of that be?
You need to use the megane one, it has 2 ports, the Clio only has one because it is non turbo'd, I had this on a recent engine build, the guy supplied a Clio one and it caused a massive vacuum in the engine, I struggled to pull off the pipe from the breather plate due to so much vacuum.
