Pressurized Oil Leak - Need a Little Help [Archive]

Bostonian1976

09-23-2007, 04:21 PM

Those of you that saw my truck on Saturday might have seen the newly-developed pressure leak that I got on the way to the event. It seems to have gotten slightly worse. I used 2 quarts of oil just going to the event and back. It seems like the oil is coming out of the cap and blowing through the engine judging by where the oil is ending up (the air filter hose that leads to the carb, the bulkhead by the fuse box, the air cleaner itself on the top half, and the oil fill stem itself, as well as the top of the cap along the rim, not to mention a good portion of the underside of the truck and engine). Has anyone ever had this before, and if so, my question is..........could the engine suddenly start builing up a lot more pressure and blow the oil out of the vented cap?

A few of you saw the truck and noted that the tube at the bottom of the oil filler tube was bolted off, and the whole pcv valve setup was made inoperable by the previous owner, and it might be the cause. The only thing that makes me think otherwise is that the truck never lost a drop of oil (from the engine anyway) before this - so it's strange that it just came out of nowhere. Does anyone know what may have caused this - I know my solution is to put in the proper non-vented fill tube, but I'm still curious why this just started up when the engine was completely dry for 3 years prior to this. Thanks in advance...

http://www.fjcruiserforums.com/gallery/data/516/Leak3.JPG
http://www.fjcruiserforums.com/gallery/data/516/Leak2.JPG

Donnie

09-23-2007, 04:42 PM

Bostonian1976

09-23-2007, 05:19 PM

The PCV system pulls vapors from the engine & re-burns them. In order for this to happen the engine has to be open somewhere for air to enter as to allow the vapors to be run thru the combustion process again..I am unsure of your condition, as I haven't all the facts, but would advise you to check that these are working..

yeah it's plugged off - so the previous owner put a vented cap on the oil fill tube and plugged off the tube on the bottom, as well as the entire pcv system. It's run completely fine for many miles like this with zero leaks, so I don't understand the change...

yorker

09-23-2007, 05:40 PM

Bostonian1976

09-23-2007, 10:46 PM

Sounds like blowby, have you lost power? If you have put the non vented cap on the oil fill AND you have a blanked off PVC system then where is the natural pressure from the crank case going to vent? It needs to be able to relieve pressure, and you sound like you have developed too much pressure to boot... :O

yeah - it's got the vented cap but I think that's the source of my oil - ends up all over the inside of the hood (just towards the very rear of the hood and the bulkhead by the fuesbox - as well as the air cleaner tube to the carb.

Terrys

09-24-2007, 06:15 AM

Bostonian1976

09-24-2007, 07:01 AM

I saw the truck saturday, but wasn't sure who was attached to which.
A simple check of compression may give clues that a ring has failed, causing an increase in crankcase pressure. If blowby is the source, you could re-connect your closed breather system, but you'll likely find your plugs fouling pretty quickly. Also check your top cap, atop the valve cover, to see that it isn't completely fouled.

Thanks! The valve cover breather has additional holes poked in it by the PO, and seems to breathe pretty well (I can see steam coming out of it when the truck is stopped and the holes are a decent size).

People were noticing that after I went down a good-sized hill in 1st and low range, when I hit the gas I had a puff of smoke from the exhaust. Does that mean it's my valves (someone else suggested that), and would bad valve seats give enough pressure to do this?

It's a mess - I was actually getting oil drops coming in through my front vents driving down the road

Terrys

09-24-2007, 08:03 AM

Does that mean it's my valves (someone else suggested that), and would bad valve seats give enough pressure to do this?

Valve and valve seat condition has nothing to do with excessive crankcase pressure. Rings and bore condition have loads to do with it.
Keep in mind, all engines will have a somewhat pressurized crankcase, irrespective of ring and bore condition, but the crankcase breather system, in most cases, eliminates build up of pressures to the extent you are seeing. Normal pressures are vented, through a positive crankcase ventilation valve, through the intake and out with combustion gasses. You engine has had this removed, and using a vented oil fill cap, is allowing pressure to escape the only way it can; up the oil fill.
My guess is you are fast approaching the time when you need to do a bottom end rebuild.

Bostonian1976

09-24-2007, 08:45 AM

Valve and valve seat condition has nothing to do with excessive crankcase pressure. Rings and bore condition have loads to do with it.
Keep in mind, all engines will have a somewhat pressurized crankcase, irrespective of ring and bore condition, but the crankcase breather system, in most cases, eliminates build up of pressures to the extent you are seeing. Normal pressures are vented, through a positive crankcase ventilation valve, through the intake and out with combustion gasses. You engine has had this removed, and using a vented oil fill cap, is allowing pressure to escape the only way it can; up the oil fill.
My guess is you are fast approaching the time when you need to do a bottom end rebuild.

sounds like fun :(

I'm mechanically inclined but have never done one before. Pretty difficult to do?

Terrys

09-24-2007, 09:44 AM

sounds like fun :( Pretty difficult to do?

Nope.

jp-

09-24-2007, 10:17 AM

Might it be that something has clogged up in the oil filter area causing the bypass to endlessly circulate? That could raise the oil pressure somewhat.

Or else you may have blown a seal somewhere.

LaneRover

09-24-2007, 10:20 AM

Look on the bright side.... ...At least your Rover is a bit more rust proofed!

Brent

Bostonian1976

09-24-2007, 10:33 AM

Might it be that something has clogged up in the oil filter area causing the bypass to endlessly circulate? That could raise the oil pressure somewhat.

Or else you may have blown a seal somewhere.

how would I check for that? remove oil filter?

jp-

09-24-2007, 12:46 PM

Bostonian1976

09-24-2007, 01:29 PM

I think it's in the oil filter housing. Don't have the green book handy. Or it could be in the oil pump itself.

Other than that, did you change anything on the engine that you can remember just before the problem started?

nothing whatsoever, except I think I checked the oil on the way down and added a quart (it was fine at that point, but not fine 20 miles later). I've been driving it all summer exactly as is - put a new distributor in last February that needs a few shims in between it and the block (it's Pertronix and there is a slight gap for some reason), but that has been completely dry all summer too

JimCT

09-24-2007, 07:21 PM

I hate to say it but I bet you have a hole in one piston. Been there and done that and it did just what you are describing. Check your compression. Jim

Bostonian1976

09-24-2007, 07:24 PM

I hate to say it but I bet you have a hole in one piston. Been there and done that and it did just what you are describing. Check your compression. Jim

how does that happen? I don't lug the engine. I don't run the engine too hot (okay my temp gauge doesn't work but it never exhibits symptoms of being too hot), timing was pretty accurate......

Terrys

09-24-2007, 10:21 PM

Anything which would cause the pressure relief valve on the oil pump to open will only bypass pump output back to pump input.
Check the oil feed tube which runs from the block to the head. Don't put a close system cap on your oil fill pipe till you plumb up the breather line, or you'll very likely blow your front seal. If you had holed a piston, you would have noticed it in both performance, and laying down a smoke screen, not to mention plenty of pissed off people behind you.

daveb

09-25-2007, 08:19 AM

I was talking about this with one of the folks who tried to help at the event.
It is crankcase pressure, not oil pressure. It is blowing out of the nipple at the bottom of the oil fill tube straight into the air current from the fan.

He is using a SIII filler neck with the top cut off to allow fitting of a breather style cap. The bolt/hose plug on the filler neck degraded and cracked.

It could be a hole in the piston or it could be a bad ring or rings. You might not notice the perfromance drop. Most likely it is a probem that has existed and was only noticed because the makeshift plug one the breather nipple failed.

You can lose a cylinder completely on a 2.25 and barely notice, so it isn't a stretch to say that a hole in the piston would go unnoticed, especially if it formed gradually. That said, i don't think that is the problem here. In any case, a compression check is easy and will tell the whole story.

The 2.25 on my last 88 had quite a bit of blowby, but ran great 62-65 mph all day long, made a few long trips in it that way sans difficulty.

If the engine is providing sufficient power, it is well to leave it alone and simply fit a decent PCV system to keep the engine bay a bit cleaner. It ain't rocket science, folks.

Anything which would cause the pressure relief valve on the oil pump to open will only bypass pump output back to pump input.
Check the oil feed tube which runs from the block to the head. Don't put a close system cap on your oil fill pipe till you plumb up the breather line, or you'll very likely blow your front seal. If you had holed a piston, you would have noticed it in both performance, and laying down a smoke screen, not to mention plenty of pissed off people behind you.

daveb

09-25-2007, 08:21 AM

got the cork gasket on that dizzy?

nothing whatsoever, except I think I checked the oil on the way down and added a quart (it was fine at that point, but not fine 20 miles later). I've been driving it all summer exactly as is - put a new distributor in last February that needs a few shims in between it and the block (it's Pertronix and there is a slight gap for some reason), but that has been completely dry all summer too

Bostonian1976

02-03-2008, 07:13 PM

Donnie

02-03-2008, 08:34 PM

per my other post - I finally checked compression and it was 135-145 on each cylinder. If I had to guess, oil seems to be coming from the breather cap on top of the valve cover and being blown back by the fan. Why would that happen?
Bad oel rings can give you a false comp reading as the oel leaking by them can actually seal the upper comp rings, thus raising, not lowering your comp test results..........

Bostonian1976

02-03-2008, 09:10 PM

Is that common? :(

Bostonian1976

02-03-2008, 09:40 PM

all plugs were dry if that makes any difference

Donnie

02-03-2008, 09:51 PM

Is that common? :(
what can happen to rings: they can wear prematurely from dust entering the engine through a neglected air filtration system, they also can sieze in the piston grooves, usually from using inexpensive oel or infrequent oel changes..the top comp ring, not the oel ring can break either from preignition, lugging the engine or over reving, advanced timing or low quality gas....faulty oel rings usually are indicated by excessive oel consumption, exhaust smoking when decending a long grade, foot off the throttle..this is only a touch on the subject & by no means a complete diagnosis of worn rings....Best to get you a manual and study....Oh yea, U did say that your PCV system was XXXXXXXXX....toss that into the mix...

Bostonian1976

02-04-2008, 09:33 AM

so uh - where to begin? sounds fun

someone at the metal dash event did notice that, after a long descent in first and low, when I hit the gas I smoked a bit (from the tailpipe). Normally though there is ZERO smoke....just a bit of black exhaust from probably running too rich.

I pulled the plugs too and they were all black (but dry)

The third plug had a pool of oil below it

Bostonian1976

08-10-2008, 09:07 PM

I think I finally narrowed this down. I had a steady drip today from the top of the oil filter canister (where it comes apart) after driving at 55 or so for 10 mins. Is it at all conceivable that a leak from there would spray up onto the oil fill tube and onto the bulkhead? Thanks

graniterover

08-11-2008, 07:31 AM

It drips down onto the driveshaft and sprays back up.

Bostonian1976

08-11-2008, 08:12 AM

It drips down onto the driveshaft and sprays back up.

this would be awesome if this is it. No blowby would obviously be a good thing.

is this a common occurrence? does the seal for the oil filter just blow?

sven

08-11-2008, 09:56 AM

Most oil leaks Ive delt with always leaked down not up. Not sure of a spinning driveshaft would make oil spray upwards like that. That seal is probably just leaking because of the excess blowby pressure.

daveb

08-11-2008, 10:39 AM

hey bosto-

pull the filter and replace it. while you are in there, make sure there is only one seal. sometimes there can be an old one stuck in the groove. dental pick to pull it out. also change the bottom seal while you are in there. I've also had sender units leak through the body of the unit so if the filter checks out then change that too. my old volvo 122 did that for a while before I figured out wtf was going on. lots of stuff in that area that can leak, clean it all up and watch while you run the engine in the driveway. you will find it...

I think I finally narrowed this down. I had a steady drip today from the top of the oil filter canister (where it comes apart) after driving at 55 or so for 10 mins. Is it at all conceivable that a leak from there would spray up onto the oil fill tube and onto the bulkhead? Thanks

Bostonian1976

08-11-2008, 11:49 AM

hey bosto-

pull the filter and replace it. while you are in there, make sure there is only one seal. sometimes there can be an old one stuck in the groove. dental pick to pull it out. also change the bottom seal while you are in there. I've also had sender units leak through the body of the unit so if the filter checks out then change that too. my old volvo 122 did that for a while before I figured out wtf was going on. lots of stuff in that area that can leak, clean it all up and watch while you run the engine in the driveway. you will find it...

thanks a lot. first of all - 122's are awesome. I've always wanted a coupe S.

I ordered the filter and O ring from RN this morning, so I'm hoping this is an easy fix - taking the truck out to the Cape this week for a little beach time so I need it to not spew oil everywhere :)

This seems to be the source though - and you're right the oil sender body points in the exact direction of the fill tube - could be that. I have no idea where to get a new one though as it's a VDO unit.

wish me luck...

daveb

08-11-2008, 02:47 PM

try here:

http://www.egauges.com/vdo_indS.asp?Sender=100PSI_VDO&PN=360-086

I have no idea where to get a new one though as it's a VDO unit.

wish me luck...

Bostonian1976

08-11-2008, 03:07 PM

try here:

http://www.egauges.com/vdo_indS.asp?Sender=100PSI_VDO&PN=360-086

thank you again! any idea on threads for this thing?

daveb

08-11-2008, 03:55 PM

heh heh you are one your own there. pull the old one out and see what it looks like.

thank you again! any idea on threads for this thing?

Bostonian1976

08-11-2008, 04:07 PM

Bostonian1976

08-11-2008, 04:17 PM

okay I ordered that sender - thanks Daveb for the suggestion...

Bostonian1976

08-11-2008, 04:18 PM

okay I ordered that sender - thanks Daveb for the suggestion...

Linus Tremaine

08-11-2008, 07:39 PM

sounds like you need to clean off your engine and then drive it. Its hard to tell where a leak is when oil is everywhere.

Bostonian1976

08-12-2008, 08:26 AM

sounds like you need to clean off your engine and then drive it. Its hard to tell where a leak is when oil is everywhere.

it's only on the side where the oil filter is, so I'm hoping that means it's coming from something like that. Now that I think about it, all seals on the left side of the engine (I guess that is just the oil pan) are dry.....*fingers crossed*

once those parts go on this week I'll know more.....

daveb

08-12-2008, 09:46 AM

hey

well, you are welcome, though I would hgave tried to pinpoint it first. don't you have two senders, one for the gauge and one for the light?

okay I ordered that sender - thanks Daveb for the suggestion...

Bostonian1976

08-12-2008, 10:55 AM

daveb,

yeah I would try to pinpoint it first as well, but I leave for a trip this weekend and I want the Rover for it....at this point I'm just starting to replace things because time is short, ya know? (plus this has gone on wayyyy too long...)

it does have two contacts on the sender, one for the light and one for the guage - but, there is no light on the guage....

I imagine the sender is probably bad anyway, so what better time to replace it....

daveb

08-12-2008, 01:00 PM

you don't have a green oil pressure idiot light like just about every other series LR made?

daveb,

yeah I would try to pinpoint it first as well, but I leave for a trip this weekend and I want the Rover for it....at this point I'm just starting to replace things because time is short, ya know? (plus this has gone on wayyyy too long...)

it does have two contacts on the sender, one for the light and one for the guage - but, there is no light on the guage....

I imagine the sender is probably bad anyway, so what better time to replace it....

Bostonian1976

08-12-2008, 01:31 PM

you don't have a green oil pressure idiot light like just about every other series LR made?

nope. the guy that rebuilt my truck apparently was not a big fan of idiot lights....I don't have any

guages are the older style with no lights inside them, and the black panel has no lights either.

oh and my oil pressure reads full tilt, my water temp reads zero and my tank reads full all the time :)

daveb

08-12-2008, 02:17 PM

gotcha. sounds like things are "all good" there. except for the solid chunk of ice with the water at zero!

:)

wonder if the VDO sender is fitted with an adapter for the 1/8" NPT to fit into the british threads on the oil filter housing. that could be a leak source too. better see how that seals up while you are in there.

good luck!

oh and my oil pressure reads full tilt, my water temp reads zero and my tank reads full all the time :)