Technical Oil leak from cambox?

[rawill]

It is hard to tell exactly where this oil leak is coming from, but after spending lots of time cleaning everything I see oil is back all over the cambelt end of the motor.

It appears to be coming from between the cambox and the head. The oil goes over the the block to the fulepump and down to the filter, it also goes out towards the cam belt and is blown back over the brake booster.

I am thinking I need to take the cambox off, or just check the bolts for tightness, before I do that I thought I would ask here incase this is an issue others have had. It does not appear to be an issue in my 70s with the same km on the clock.

Down on Power
This only happens sometimes, most of the time it behaves as it should power wise. But sometimes it will only do about 75-80 kph. Accelerator to the floor and the econ guage off the scale.

I think carburettor but why would it only do it sometimes.
First tank of petrol in this car returned 36.27mpg
Second tank of petrol returned 32.57

I do my check brim to brim and zero the trip meter each time.
This might be related to above but the time it is down on power is for only a very short time.

 

[alexGS]

1116cc or 1299/1301cc... and even possibly 1372cc... Oil leak from cambox - pools around the head bolts? - very common problem in the old days (this engine design goes back to 1969) - my solution is Loctite Master Gasket 518 but you do have to take the cambox off first and clean it up. Belt off, all bolts undone progressively... used to seem like SUCH a job, but I have to say, by the standards of modern engines, it's a walk in the park.

Master Gasket 518 the translucent red goo, not the silicone sealant. The 'gasket' is just a joke really - a thin bit of brown paper - so don't bother with it at all.

However, often the leak is just from the cam cover (and oil runs down) - that merits a new gasket. It's a much thicker, compressible gasket but be careful not to overtighten the six 10mm nuts, as those are only 6mm threads. I used to use silicone sealant 18 years ago, which works in a pinch, but it's better to avoid silicone sealant if you care about unblocked oilways. I was young (12) and didn't know better (though my Dad did and wasn't very happy when he found out WHY Mum's car didn't leak any more). I thought I'd done a really proper job, as I managed to use up most of the tube. These days, with couriers and credit cards, it's easier to get the right gasket.

Since you mention the oil being mainly at the cambelt end of the engine, I have to wonder whether it might just be the seal behind the cam pulley. Those go hard with heat and age, and usually need replacing when the cambelt is changed, but few people bother. It's relatively easy to change. The cam pulley is keyed to the camshaft.

Both the cam seal and the joint between the cambox and head require about the same amount of work to fix (air filter/cambelt off, etc.) so I think you should do both, to be on the safe side. Unfortunately I can't remember what size seal it is, but anyone who has 'spares' from gasket sets will have plenty to spare.

As for the occasional bad performance, blocked carburettor jets cause that - they can un-block and re-block. In this case it would be a blocked main jet on the secondary system. Best way is to clean the carburettor out with compressed air. If you've already done that, suspect a low float level (depriving the secondary main jet of fuel). These are both just guesses, though. It's hard to diagnose performance problems without driving the car Usually an ignition fault would cause a violent misfire at various speeds and loads, which is why I'm leaning towards a fuel problem as I'm getting the impression the power just peters out at the mid-top range. Another possibility - low fuel pump output which leads to the float level being low.

I know you're wondering how a lack of fuel can lead to additional fuel consumption - and fair enough too! - but sometimes if the carburettor is operating in a manner other than intended (e.g. full throttle when full throttle isn't normally necessary) then it can increase the fuel consumption.

I have had the case where blocked jets caused really GOOD fuel economy and a shower of sparks from the exhaust at highway speeds, a lack of power followed by melted spark plugs and light-grey exhaust pipe. Which does make me wonder if I'm on the right track here or not! But it gives you a bit to think about.

The opposite problem to a low fuel level is possible, too. If the needle valve sometimes fails to shut off the fuel (bit of dirt in the seating), the carburettor will literally 'flood' - fuel washes over the bridge into the venturi. Mixture goes way too rich (with obvious effect on fuel consumption and carbon-fouled spark plugs). I don't think that would reduce power at the top end, but the idling would certainly disappear (become very slow and rough). Maybe the next time you have this problem, try dipping the clutch and report whether the engine idles correctly.

-Alex

 

[fordliu]

Thanks for the info., I think i can use it on my car.

 

[alexGS]

Possibly not!

Unless yours is the 1372cc, you and uCof both have the FIRE engine, where I was writing about the older-design 1116cc/1299-1301cc/1372cc engines. They're the ones where the cam cover is on an angle and the camshaft is in a housing that's bolted to the cylinder head.

The FIRE often has a leak from the aluminium cam cover, which has a rubber seal - cheap and easy to replace. The camshaft is mounted directly in the cylinder head, so there's one less join and one less place to leak.

-Alex

 

[Chas Uno]

Unless yours is the 1372cc, you and uCof both have the FIRE engine, where I was writing about the older-design 1116cc/1299-1301cc/1372cc engines. They're the ones where the cam cover is on an angle and the camshaft is in a housing that's bolted to the cylinder head.

I thought most of the non turbo 1116/ 1299/ 1301 engines had block mounted distributors Alex?

 

[rawill]

Thank you Alexgs, as usual a very through reply. You must be fast typist!

It must be from the cambox, and possibly the seal. I will do those, as it is definitely not the cam cover. I have been very careful to check that as that is what I suspected.

I will clean out my carb again, but when I bought it it had 2 fuel filters on it. and I will check the float level, should have done it when I had it off last time.

Thanks again.
Robin

 

[rawill]

I thought most of the non turbo 1116/ 1299/ 1301 engines had block mounted distributors Alex?

1986uno45s, Yes you are right, but I think you are misunderstanding what alex is saying. If I read it right, he is talking about exactly those engines you are refering to. He never mentions the distributors though.

 

[alexGS]

1986uno45s, Yes you are right, but I think you are misunderstanding what alex is saying. If I read it right, he is talking about exactly those engines you are refering to. He never mentions the distributors though.

LOL - thanks, I'm confused now
As you rightfully point out, I wasn't talking about distributors

It would be a lot better if I had some pictures of non-FIRE engine parts to post on this thread. So I dug out a couple of pictures from olden days - this is an Uno 1301cc cylinder head fitted to a 1498cc motor. In the first picture you can see the thin paper gasket I was talking about (the camshaft housing has been removed). In the second picture you see the separate camshaft housing. If the top of your engine doesn't look like this, advice in post #2 won't apply (I know yours does, Robin!)

-Alex

 

[Chas Uno]

1986uno45s, Yes you are right, but I think you are misunderstanding what alex is saying. If I read it right, he is talking about exactly those engines you are refering to. He never mentions the distributors though.

LOL - thanks, I'm confused now
As you rightfully point out, I wasn't talking about distributors :thumb

[embarrassed]

Don't ask me how, but somehow I got the talk of camshafts and 'block mounted' confused with distributors! Probably something to do with it being 6.30am and me still being half asleep.

[/embarrassed]

 

[rawill]

LOL

I am glad to see we are communicating with people not just keyboards.

I haven't done anything about the oil leak yet, but it will happen this week. I think it is the oil seal. I am going to double check.

Been a bit busy here with New Zealand's premier cycle tour, The Tour of Southland. And our team won!!

Heath Blackgrove took out the tour for the Zookeepers - Cycle Surgery Team, and they took out the Top Team prize. Check out my pictures on Facebook.

Nothing to do with Fiat Unos except I took four of them home in my Uno last night.

 

[alexGS]

Cool!

Unfortunately I never bother to use FaceTube or MyBook or whatever it's called on the Interweb these days...

Actually I hate Facebook with a passion and have convinced myself that if I used it, I'd get even less work done while filling my day (and others) with all the sorts of trivial details ("Jason is eating a sandwich!") that get broadcast far and wide. Plus, the interface annoys me (it's like eBay meets forums meets a news website) and it's sooooooo slow and unreliable, I haven't seen as many red X's since I used Word 6.0 as a photo album once

-Alex

 

[rawill]

I only got into Facebook because of our son and daughter are there. I never thought I'd get into it at all, but there you are.

I have one pic to add on the Tour, one of the winning guy getting married, between the end of the tour and the prizegiving.

I officiated at the wedding, and I was one of the team, driving the support vehicle, which as you can see is not a Fiat Uno.

However I dd get 4 of the riders in the Uno to take them home from the after match party.

Sadly it was dark, I didn't have my camera and so I have no photo!:bang:

 

[rawill]

Alexgs, thank you.

Cam seal
I would not have thought of the cam seal. I got a box of tricks from Mal today and put the new cam seal in this afternoon.

The old one was as hard as concrete. And you could see where the oil was dripping from the seal. Hopefully it will be all good now. I never took the cambox off.

Electric Windows
I also got two Tipo electric window regulators to try in my Uno.
It looks like they will work with some minor modifications.

I have only fitted it in temporarily, the window goes up to about 1-2 mm from the top. Unfortunately I broke the little plastic slide on the window so I will have to make a new one. :bang:

Rattles
I put in 3 new engine/gearbox mounts hoping it would get rid of some knocking on rough road. It didn't work, I have new mounts but still old rattles.

I now suspect my new (10000km front shocks - Munro) are not as good as I thought, and that I will need to try some brand new ones.

I can feel the knocks under my feet. I have checked all the suspension mounts are very tight.