General Sigh . . oil leaks

[lazylobster]

So, near on 300 mile usage of Valentina this weekend gone. A lot was done at speed (70mph whoop whoop) on the M25, M40 and M4. She seems to be fine at speed. Quite impressed with 2 up and a small amount of luggage.

However, she is throwing a bit of oil about in the ol engine bay. Seems to be some over the cooling flap, out to the dist. heat shield and coil area.Some around the carb on top of the engine. :bang:

Not oil dipstick as I replaced this few weeks ago with new item.

I think the top of the engine is that some of pipe work is loose, suction and oil breather. The biggest concern is around the right hand side of the bay.

Reading the forum, it seems gasket /rocker cover or push rod tubes. Someone mentioned spring loaded tubes?

Can some kind soul educate me please?

Thanks
Rob

 

[Vitesse]

The only way you are going to be sure Rob is to drop the engine and gearbox out. You can get the thermostat housing off in situ but tbh it’s a lot easier and quicker to drop the lot out and remove the tin work to see where the leaks are. From what you say it does sound like the push rod tubes but you won’t know for sure without checking out the whole thing.

You can get sprung pushrod tubed but to be honest if the concertina type are fitted with decent seals then it shouldn’t present a problem. The seals can get trapped when the head is pushed down and it screws the seals eventually, so you need to make sure that it’s done slowly and double check everything before bolting down.

Below is a picture of a bare engine so you can see the potential offending area.

Tony

 

[the hobbler]

Well done on the mileage you have covered---it's what there designed for. I have just got back from Italy where in order to get to/from a Raduno, we covered 390km in 1 day in a 1963 500D---the little engine just bumbled on.
With regard to the 'Spring-loaded' push-rod tubes---look at Axel Gerstl's site (as an example--other people can supply theses tubes)---"engine parts and gaskets" and then--"oil supply". I use the thicker of the available 'push-rod tube' seals. The beauty of these tubes is that you can fit the head onto the engine, and the tubes can be closed up just enough that you can then fit them individually---much easier than trying to align all the tubes up as you drop the head back on. Where does your rocker-cover breather come out to? Oil from this can spread over the engine. If the oil is blowing out onto the distributor, there is a fair chance that the leak is from the head area, and being blown out by the cooling fan.

 

[Bleeding Knuckles]

So, near on 300 mile usage of Valentina this weekend gone. A lot was done at speed (70mph whoop whoop) on the M25, M40 and M4. She seems to be fine at speed. Quite impressed with 2 up and a small amount of luggage.

However, she is throwing a bit of oil about in the ol engine bay. Seems to be some over the cooling flap, out to the dist. heat shield and coil area.Some around the carb on top of the engine. :bang:

Not oil dipstick as I replaced this few weeks ago with new item.

I think the top of the engine is that some of pipe work is loose, suction and oil breather. The biggest concern is around the right hand side of the bay.

Reading the forum, it seems gasket /rocker cover or push rod tubes. Someone mentioned spring loaded tubes?

Can some kind soul educate me please?

Thanks
Rob

Hello Rob, Yes sadly it's a way of life with these engines. I too have leaks
As Tom @ the hobbler has stated the pushrod tubes are a pain and I have gone for an adjustable tube from a VW beetle for my next engine. It seems that no matter how careful you are with the cleaning, preparation and fitting of the seals they will weep eventually - my front pushrod tube is 'p*****g' oil out and this is contaminating the cooler flap area, distributor and heat protector shield too The good thing about the VW seal is that they are larger and tapered so that you can get the head on and then fit the tube after it's all torqued down. My other leak is from the rear crankshaft pulley seal in the timing cover. The daft thing is that I removed a good (not leaking) seal and fitted a replacement only for that to fail once the engine was fitted into the car Bummer or what???? I would just check the front of the rocker box cover too, seals can go in this area too.

Ian.

 

[F123C]

Many miles at 70 mph in a 500?

That's some workout.

So now your 500 is 'sweating'

AL.

 

[BambinoClassic]

Maybe start with the simple bit and check your exhaust mounting bracket bolt holes?


You wouldn't be the first to have oil spraying out of these, and it does preference the right hand side when spraying oil from these.
Make sure they aren't loose / a bolt gone missing leaving them open!

 

[lazylobster]

Thanks for all the suggestions. Some explority work to be done for sure.


If it is the tubes, I've come across silicone thick seals. Suspect these may last longer than rubber.



FYI


https://www.fiat500ricambi.com/fiat500/Engine+parts/MO1077



Cheers
Rob

 

[fiat500]

Brilliant work there Rob, making the car "sweat"! (a la F123C). As has been said before, oil leaks can have a variety of sources and have a habit of coming back. The first thing I do is to degrease the areas affected and then after a shortish journey, check to see it's easier to locate the leak.

In the past, on my car, I think I may have confused what was actually a timing-cover leak with that of the crankshaft seal and one from a breather hose which needed pushing more firmly on with a rocker-cover gasket leak.

You will presumably want to avoid doing more dismantling than necessary so it's wise to avoid jumping to conclusions.

Although I endorse what people are saying about the potential fragility of the push-rod tube-seals, (particularly on the 499 engine), I have found that if they are fitted carefully at the beginning and a small amount of sealant is used to supplement the rubber seals, they last (at least) 16,000 miles.

 

[lazylobster]

Brilliant work there Rob, making the car "sweat"! (a la F123C). As has been said before, oil leaks can have a variety of sources and have a habit of coming back. The first thing I do is to degrease the areas affected and then after a shortish journey, check to see it's easier to locate the leak.

In the past, on my car, I think I may have confused what was actually a timing-cover leak with that of the crankshaft seal and one from a breather hose which needed pushing more firmly on with a rocker-cover gasket leak.

You will presumably want to avoid doing more dismantling than necessary so it's wise to avoid jumping to conclusions.

Although I endorse what people are saying about the potential fragility of the push-rod tube-seals, (particularly on the 499 engine), I have found that if they are fitted carefully at the beginning and a small amount of sealant is used to supplement the rubber seals, they last (at least) 16,000 miles.

Sage advice good sir. I'm not rushing into anything as about to leave on a long business trip so I'll tackle when I get back.

I like to give the car a work out and make her sweat She did great at speed, seemed very happy and surprisingly had plenty of oomph.

She held at 110kmh ish very well even up slight inclines. She is a R model, so has the 595 126 lump in her and I upgraded from a 24 to 28 carb to release those last few ponies. Added electronic ignition (powerspark) and new ignition components. The new spark plugs alone must be good for + 0.2 BHP :slayer:

So, question, as it seems there is some surprise that the car would be used in this manner on the motorway. Although I know 500's modus operandi is not for motorway cruising, is there any harm / concern with using for long distance at speed? I've always thought that cars drive better if used. Apart from some oil spray, which seems common and I had it before the long / speed drive. She drove great.

Final add, petrol cost for the trip was silly cheap. God, I love this car

Regards
Rob

 

[fiat500]

There's some contradiction here in that a lot of discussion is made about jacking up the revs and the power output (and the noise!) of these engines whilst in some quarters there is an underlying sense that it's not really up to the job of extended, high-speed motoring.

If your engine is unmodified you're correct in that you're doing it more good than harm by taking it over long distances. The 594cc variant should be good for an indicated 70mph and my 652cc seems to have the potential to give more than that.

When not in a rush I like to pootle along at between 55 and 60 mph and only move up to 70mph when I have a bit of motorway to eat up. On our local main road...the A9 from Perth, which is about 110 miles, I recently thundered along non-stop at 60mph (the speed limit for much of the way) and the car felt as solid and reliable as any modern.

I would chicken out of going at 70mph all day as I like to have a bit of power in reserve and have constant fearful visions of the speed that the internal components are moving at, but if your engine is in good shape and seems to thrive on it i think you're right to trust your instincts that the engine can cope with it.:worship:

 

[Vitesse]

I think you would be hard pushed to find a 500 without some form of oil leak. A major oil leak is obviously a concern but minor ones, so long as you keep an eye on the oil level and the pressure light shouldn’t cause a problem.

I think a lot of people forget that most of these cars are 40+ years old and start to try and maintain them like a modern i.e. zero oil leaks. These are pretty bulletproof engines, so long as major problems aren’t overlooked.

My 650 eBay engine that I bought, when I stripped it down was coated in oil once I stripped the tin work off, mostly from the pushrod tubes, crank seals but it still bench tested and ran really well. The positive underneath all that grime was a lovely shiny engine block.

 

[Toshi 975]

I think you would be hard pushed to find a 500 without some form of oil leak.
I think a lot of people forget that most of these cars are 40+ years old and start to try and maintain them like a modern i.e. zero oil leaks. These are pretty bulletproof engines, so long as major problems aren’t overlooked.

The designs for the 500 engine would have been on the drawing boards in the mid 1950's and considering that the resulting engine would have been restricted to the technology and materials available at the time it has stood up remarkably well. I would guess that the concertina type push rod tubes with the thin black seals were the best solution at the time. Limited by the characteristics of the seal material as the tubes would have been quite expensive to manufacture. The 'spring' in the tube coming from the concertina sections. Had the design been a major flaw then it would have been addressed rather than millions of engines produced using it. With the 126 engine the solid push rod tubes were simpler, so cheaper and relied on the 'Spring' coming from the the wider seals. This design appeared to be good enough for a few million more engines.
The red silicon based seals are generally thought to be an improvement on the originals though.
So why the leaks? Bearing in mind that many of our cars have been through the phase of being regarded as worthless old hacks and treated accordingly they have arrived in a new age beyond their intended use but many will have suffered the effects of neglect and abuse. The push rod tubes are a relatively delicate engine component and in my experience of engine rebuilding I have come across quite a few tired or damaged ones. Most common problem has been the ends where the seals fit being bent out of shape so need to be straightened and the fit tested either into the head or the crankcase. Some have taken a knock and if they are too much out of alignment I scrap them. The concertina type can tire and I have refreshed them by inserting something like a Tommy bar in each end then applying pressure and rotating the tube to literally bend the concertina section.
Either way you must take great care when fitting the head as it should stop a little short of the head gasket resting on the seals. At this point I rotate the tubes by hand to make sure they are not snagged on a poorly fitted seal.