Pinto Oil Spurting Out Of Filler!

[Guest slimesub5]

Hi, I have a 2L pinto that has been part rebuilt.

Skimmed and re-worked injection head 10.3:1

New valve guides and seals

New FR33 cam & followers

New big end & little end bearings

Cylinders check, no scoring, no signs of wear. (Didn't re-ring as all "looked" good)

Currently using a 1.6 carb to bed in Cam

All runs well.

Above 4000 rpm it blows oil out of the filler! So did a warm compression check:

Dry

1- 140

2- 145

3- 145

4- 140

Wet (squirt of oil)

1- 146

2- 154

3- 154

4- 147

I thought generally these were ok? Probably a bit low because because of long duration cam?

 

So I turned to the crankcase vent system. Fitted a catch tank, pipe from new filler cap with hose conn to tank, ground bottom off of crankcase vent elbow and removed insides, ran hose to ventilated catch tank.

 

Ran up again, ok to 4k, above this - woosh! New filler cap popped out ( was a loose fit though ) Oil everywhere!!

Took cam cover off to check valves, followers and spray bar. All ok, oil dripped out of spray bar when turned over on starter, when started it really did flow out and overflow, just at tick over for 2 seconds! Could the spray bar holes be too big, filling up the cam cover? How can I check this?

 

I throw it to the masses, I'm thinking rings? Could it be anything else? Am I missing something?

[speedtripledan]

the cap should vent to atmos not a tank others have put both crankcase vent and filler cap to a tank and had oil blow out in the way you describe

[Shaft]

Agree with Dan, mine was solved by simply disconnecting the rocker cap breather from the catch tank.

There wasn't sufficient 'volume' of air passing through the catch tank filter and as such was causing massive crank case back pressure.

 

HTH,

 

Nick

[Longboarder]

Blowing oil out of the filler or blowing the filler cap out suggests high crancase pressure. Only likely to happen on a very worn engine or in the presence of an error in vent plumbing. We have all seen old bangers that use a pint of oil every 100 miles. But they burn more than they blow out.

A properly designed catch tank vents to air. It feeds to its base compartment and vents out the top and catches the oil with internal baffles and/or mesh. It doesn't need one of those silly tiny filters which get oil soaked and stop air flow virtualy sealing the system so it and the crankcase pressurise.

Take the ends of both vent tubes to old pllastic bottles and just stick them in, not sealed. Run the engine. See what blows out and from which vent. You should find the pressure is mostly crankcase. Oil shouldn't blow out excessively from either. If the cam cover is filling with oil faster than it can drain due to excessive cam lube holes then the cam vent will pour oil after a while. If they both flow heavily then the engine is too wornto use without new rings and a hone at least.

Incidently you can fit a larger vent elbow in the crankcase. Burtons do them. But try to clarify the problem first.

 

Nigel

[Guest slimesub5]

Thanks for the answers guys......

Will try again tomorrow with both hoses disconnect from catch tank into clear bottles so I can see what's happening.

 

(Originally had standard vented filler cap & crankcase vent to inlet manifold when it first blew oil out of filler.)

 

I have a burton's vent elbow but too loose a fit in the rubber sleeve where the standard one fits. Should the burton one fit straight in the block?

[Grim]

140psi sounds low to me, mine was 170/175, on a bog standard (cr 9.2:1) pinto. Did you have the throttle fully open during test?

is it run in? few hundred miles at least?

[Guest woolly]

Agree with Nigel probably the spray bar.

Years ago fitted a new cam kit to customers car fine around town blew the oil out at steady high speed. Fitted the old bar back and all was well with the world.

Some rocker covers have a oil defection plate under the filler

 

[Snapperpaul]

We've had this issue on several Pinto's

You need bigger vents and tubes from rocker and block, 16mm min some use 19mm from the block and a large throat vent filter on the tank

Tank should be as high ad the top of the rocker cover.

Another trick is to run the vent pipes from block to rocker and T to the tank this way the oil most flows between crankcase and rocker but excess pressure goes to the tank

I'm currently modding breather pipes and tank.

 

Compression ratio is low, maybe the extra duration/ overlap of the cam is causing this, perhaps retarding the cam timing a couple of degrees will gain some back as Will a thinner gasket.

There's is a lot of confusion with static compression ratio and dynamic, whilst 10.3 to 1 sounds right valve overlap duration with a radical cam will reduce actual cylinder pressure, your looking for 190 to 200psi ideally. I think I run high 170's to low 180's currently and plan to work this to low 190's using a 295 duration cam

[Shandylegs]

If you are still running a single carb why are you using a catch tank when you could still be using the inlet to provide a vaccum to pull all the gasses out of the crankcase?

 

- Fist thing to check is that your cam cover has a deflection plate below the filler, some do, some don't (As there is now no vaccum being created by the inlet, there is alot of oil splashing around the head looking for a way to get out). If there isn't, fit one.

- At the same time fit the crankcase breather properly. Remove everything Ford fitted, the Burton elbow does fit directly into the block

- Vent everything through to the catch tank but make sure the catch tank has enough breathing to the atmophere (You wouldn't beleive the amount of times I've seen masssive bore hosing used from the crankcase and cam cover, only to see a little K&N filter fitted to the catch tank - these only have something like an 8mm internal bore!)

 

There are lots of other things you can do but this starts costing loads of money to sort properly. Do a search on here or google as there is lots of info on this.

 

Thanks............

[Guest mower man]

This can be a prob , looking at some of the above posts my engine should p--s oil out i,it does not ,there is no defector in the cam cover, cam cover and crankcase are vented to tank which has a breather on top ,the tank top is only push fit . hose size is important, mine is 16/17 mm to suit fittings I have used i.e hydraulic bulkhead the tank is fed low down but is above cyl head .Ihave a shortened/extended sump but only run std oil capacity and the sump is partialy windage plated , I don't know that any of this will help but there may be things you have overlooked mower man ps Nothing is fed into the inlet ,this is not a mistake ,I don't want a 2 stroke!!

[Guest slimesub5]

Ok.......

Changed the spray bar off of an old 1.6 that I know is ok. Holes looked about the same, but changed it anyway.

Put some ptfe tape around the filler cap to make a tight fit.

Ran hose from crankcase breather into a clear bottle & filler cap hose to another clear bottle.

Warmed engine up, at tick over: no air or oil from filler, gentle flow of "fumes" from crankcase breather (these condensed into water).

Reved it up, 2k, 3k, 3.5k all ok, flow of air from crankcase increased a little. Not pressure from filler cap.

Took it up to 4k bit of a sput of oil from filler vent, about a few tea spoons worth.

Took it up to 5k then 6k, pop, filler popped off and oil everywhere again. Dribble of oil from crankcase vent!

 

What do we think then gentle folk? I can only think rings?

[Guest slimesub5]

If you are still running a single carb why are you using a catch tank when you could still be using the inlet to provide a vaccum to pull all the gasses out of the crankcase?

Only using a catch tank because I was trying to sort the oil spurting out of the filler!!

[Guest slimesub5]

Think I will try running with the oil level on the "low" mark on dipstick. (Now clutching at straws!!)

Was on max, now half way after oil spurting out of filler!!

[Guest mower man]

Have you got accsess to cyl leakoff equipment ? , freindly garage ?etc this would pinpoint problems bore/ring wise may evenbe worth paying to have it done ,any one competent should breeze it in half an hour and you would have a definitive answer mowerman

[Guest slimesub5]

Have you got accsess to cyl leakoff equipment ? , freindly garage ?etc this would pinpoint problems bore/ring wise may evenbe worth paying to have it done ,any one competent should breeze it in half an hour and you would have a definitive answer mowerman

 

I think that's a good idea, not sure how much they are to buy?

 

Just put a bit more PTFE tape around cap, oil half way up dipstick, it doesn't pop out now, and dribbles a very small amount of oil at high revs, but the crankcase breather is blowing what looks like lots of steamy fumes!!! It is condensing into water doh! Or is this normal?

 

Now really confused, possibly head gasket?

Edited December 9, 2012 by slimesub5