I'm tinkering with a friends 200 euro F4 van (845cc zenith 28if carb), got it running, new plugs/dizzy cap/rotor arm/carb cleaned out etc but it's got a fair bit of pressure in the crank case (dipstick tube/oil filler etc) it runs better when the breather pipe on top of the engine is blocked. Funny thing is there's very little smoke and it has plenty of power through the rev range. The old plugs were oiled up and it ran like a bag of hammers when we picked it up so I'm worried the rings are shot. Any advice? I'm thinking of going for a CT and if it passes nursing the engine to its grave before replacing. How might I best get it through the emissions test? I was going to block the breather to the carb, put 20/50 in and lean out the mixture as much as possible. Any advice here, or is it new motor time? Could be an excuse for a turbo swap as the car is in great condition.
- Thread starter DaveP
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malcolm
& Clementine the Cat
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It's worth checking if you have the restrictor in the breather hose that connects to the manifold. It's a plastic insert that pushes up inside the hose with a 1mm (ish) hole in it to restrict flow. Without that any engine will run badly.
Blocking the hose off won't make emissions from the exhaust any worse so long as you block the connection to the inlet manifold. On my MG the hose from the rocker cover is routed to the ground.
Difficult to suggest settings for emissions. Generally make sure the points gap and timing are OK, that the air filter is good. A starting point for the carburettor mixture screw is generally 1.5 turns out from fully closed. Sometimes the screw is fiddled with by a previous owner.
WHy do you feel you have too much crankcase pressure?
Blocking the hose off won't make emissions from the exhaust any worse so long as you block the connection to the inlet manifold. On my MG the hose from the rocker cover is routed to the ground.
Difficult to suggest settings for emissions. Generally make sure the points gap and timing are OK, that the air filter is good. A starting point for the carburettor mixture screw is generally 1.5 turns out from fully closed. Sometimes the screw is fiddled with by a previous owner.
WHy do you feel you have too much crankcase pressure?
Steve Hennessey
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Has the engine not been used for a long time? If so, the rings could be stuck in the pistons. Never block the breather pipe or you could blow oil seals and gaskets. Have you carried out a compression test?
the engine has been out of service for 6 months, we'd expected it to be a scrapper as the old owner said it wouldn't run and we were looking for a van to put a gordini engine in. We replaced the plugs and battery and managed to get a 2000rpm tickover then drove it home (10 kms.) After swapping a few bits around from a spare engine and setting up the carb (about 1 turn on the mixture screw) we got a slightly rough tickover (about 800 rpm) and full revs/power so we'd hoped to rescue the existing engine if possible, I've reset points gap and replaced all the electrical "consumables" and the engine seems fine, just this crank pressure, if we set it to just tickover (no choke, no throttle) even removing the dipstick will cause it to stall and oily fumes come out. I don't have the tool for a compression test but shall probably get one.
If the rings are stuck in the pistons would a good thrash be a possible cure or is something less agricultural in order? I'm no mechanic but it's such a lovely simple car to tinker with, I'd be very happy to have sorted a supposed non runner. Worst case there's an alpine turbo in the scrapper with my name on it. I'll check the breather restrictor tomorrow, but it seems to me the pressure is very high compared to my TL (identical engine)
If the rings are stuck in the pistons would a good thrash be a possible cure or is something less agricultural in order? I'm no mechanic but it's such a lovely simple car to tinker with, I'd be very happy to have sorted a supposed non runner. Worst case there's an alpine turbo in the scrapper with my name on it. I'll check the breather restrictor tomorrow, but it seems to me the pressure is very high compared to my TL (identical engine)
Ah the joy of cars. We changed engine/gearbox for the 1108, got a renault 5 head etc, gordini seats, fixed up the brakes and interior, replaced a driveshaft and all the ball joints and dampers. Then on the second day after we finished it got rear ended and the fuel tank blew up. Back to the drawing board, at least the dampers/balljoints and drums were ok, and the scrapper kindly let me have them for nowt
Insurance pending
Insurance pending
malcolm
& Clementine the Cat
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- Bedford UK
2 days -that must be devastating. :eek: Thank goodness for Gordini headrests. Is everyone OK?
Sounds nasty if the tank was damaged. Was there a fire? In the UK it's normally possible to buy the whole thing back from the scrapper for next to nothing and transfer the good bits to another car. Do the French work it that way?
Sounds nasty if the tank was damaged. Was there a fire? In the UK it's normally possible to buy the whole thing back from the scrapper for next to nothing and transfer the good bits to another car. Do the French work it that way?
The guy driving was sat in the car feeling for broken bones when the fuel ignited around him, hastening his exit. Few burns but nothin serious. The car is a charred wreck though, only reason I managed to get the parts off was the arches acted as a firewall.
I'm now left with all the worst bits off two f4s and no registration documents.
I'll try to get a photo on here of the before and after
I'm now left with all the worst bits off two f4s and no registration documents.
I'll try to get a photo on here of the before and after