Technical The day I changed my O ring and diaphragm

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Technical The day I changed my O ring and diaphragm

Ucof

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This writeup is in regards to this guide as written by Louie Bee - https://www.fiatforum.com/uno-guides/43921-curing-distributor-oil-leak-fire-engine-uno.html

My lil' engine has been pissing oil for a while now and after being inspired by the "Dude! What's wrong with you car?" thread, I ordered the ring I needed from ebay which was waiting for me when I got home today.

The job is an easy one in my opinion. If this were a Haynes manual, I'd give it half a spanner. I managed to do it in under an hour (after printing out the guide from Louie Bee to take outside with me) without rushing, and not really knowing what I was doing.... :D

letsgosmall.jpg

Here we have the new ring, and the printed instructions.

oiloiloilsmall.jpg

As you can see, my engine really has been pissing oil, for as long as I have had the car, and for ages before that I can assume.

distributoroffsmall.jpg

Took the distributor off easily, its a 10mm nut by the way :)

oldthinringsmall.jpg

As you can see, the old ring (the black band in the middle of the bit that sticks out from the end of the distributor - NOT the bit nearest the camera with the two nobs on, that is NOT the bit Im talking about ) is flat as a pancake and as flush as a pancake in a pancake sized hole.

fittedoringsmall.jpg

As you can see in this picture, the new O ring stands proud like an erect *****. :slayer: Rock on.

oldandnewsmall.jpg

New one fitted, old one (which was flat and as hard as plastic, not rubbery at all - I had to split it with a small flat head screwdriver to get it off!) at the side.

distributorsmall.jpg

Looking in the end of the distributor, 2 of the rods are very, very small (almost totally gone) and the other two seem to be ok. Should I replace these ASAP or, as it is working, should I leave it?

oilorpetrolsmall.jpg

I also took the air filter off so I could get at the pipe from the diaphragm a little easier (it was a BITCH to get off, I had to pry it off with a flathead screwdriver in the end as it didn't come off as easily as Louie Bee says it does! :D ), and noticed that there was a good amount of brown liquid not only round the seal of the carburettor and the air intake, but also around the pipe that goes underneath the filter was coated in this liquid. Could it be petrol, or is it more likely to be oil? What would be causing this also?

I would have loved to have taken more pictures, but my phone battery was low, and it wouldn't let me. Which sucks.
I started the car up, and the first time I did, it sounded quite rough. I had a look in the engine bay and noticed the exhaust manifold inlet wasn't connected. Put this back together, and gave it a rev, and it sounds much better now. There does seem to be a ticking noise in the distributor though. Might take it into the garage when I get it its' yearly service and get them to look at the timings too.

I had a look at the diaphragm like Louie Bee suggested...and mine seems to be knackered. I can blow and suck continually ( :yum: ), but I know the pipe is fine as I blocked the other end and there was a proper airlock. One quick phone call to dad, and I have a new (spares and repairs) entire distributor (and thus the diaphragm) on the way. However, I'm surprised that the car has been fine without it. What exactly does the diaphragm do?

Also, when I turned the engine on and it started warming up, around the exhaust manifold started smoking. Is this just the bits of oily crap that I cleaned off and that had fallen onto the manifold, and started smoking when it got hot, a kin to a frying pan full of overly hot oil?

All in all, a good guide (pictures could be better though Louie Bee (no disrespect to you for doing the guide though, just a suggestion!)) and an easy job to do yourself if you don't mind getting caked in oil.

Thanks much Louie for the guide!


EDIT - Have just been out for a 20 minute spin up and down the bypass (upto 80MPH ish) to test the car. It is mainly fine but it does seema bit "spurty" when in 2nd and 3rd gear (and first to an extent). Does this mean the timing is off slightly? It did seem to not have as fast acceleration as is 'normal'.

Charged up my phone too so i can take some pictures:

oilcablestartsheresmall.jpg

This is where the oily cable starts - is it the speedo cable?

cleanishsmall.jpg

Underneath the distributor doesn't seem to be coated in any new oil! However, only time will tell as I doubt a quick spin out would produce much!

drippingsmall.jpg

The only dripping bit is directly under the distributor, where I can only assume that old oil has warmed up and dripped down. Other than that, all is fine :)
 
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Good Job!!

My camera at the time had 1 button and no flash

I had the clicking after swapping my dizzy a few months ago. Can’t remember what it was, just make sure the rotor arm and cap are on properly.

The 2 pegs inside the distributor cap that there is not muck left of started life small, not a full peg. Don’t worry about it! You should get another one with the dizzy off your dad, or I’ll lob one in with the clocks.

My little pipe falls off, and Dunc snapped his trying to slip it over.

The brown stuff inside your air filter is poo.

Not really, it’s oil that is deposited from the closed circuit breather setup. Don’t worry most modern engines have this future of catching the oil droplets chucked out by engine breathing. Worry when the air filter is full of oil like my first MK1 ended up like. You can get an oil catch tank to collect it.

Good idea to can clean the oil up inside the filter, and clean inside the pipe that’s to the left of the air filter (breather pipe) and the gauze is meant to be inside it (called a fire trap). Give it a good clean, cos it causes other problems when blocked.

Ask your dad to check the diaphragm before sending cos it’s probs shot too.

The diaphragm (when working) advances / retards the ignition timing in relation to the manifold vacuum. You should see a big difference when it works at least 3 ponies. I could tell when my pipe sprung a leak! Flat as foook.

Splurty acceleration will probs be due to timing. Did you align the distributor rotation back up? Have you had the battery disconnected? If so, the ECU will have been reset. Maybe you blew too hard and broke the diagram. I’d remove the pipe that attaches to it, and block it off till you get a good diaphragm.

The Speedo cable comes through the other side of the bay. That would be the throttle cable your arrow points to.

If the oil inside your engine is clean, any new leak will be the same colour if you cleaned the old stuff off well.
 
Awesome, thanks :) :worship:


You should get another one with the dizzy off your dad, or I’ll lob one in with the clocks.

I will be :) He should be sending all the stuff tomorrow.


My little pipe falls off, and Dunc snapped his trying to slip it over.

This line makes me giggle more the more times I read it! :D


The brown stuff inside your air filter is poo.

5hit. :(


Good idea to can clean the oil up inside the filter, and clean inside the pipe that’s to the left of the air filter (breather pipe) and the gauze is meant to be inside it (called a fire trap).

If the thick breather pipe is fairly cracked, should I make it airtight again (get my dad to send it on over!)

Ask your dad to check the diaphragm before sending cos it’s probs shot too.

Whether or not it is, I'll be getting it anyway. Will possibly change the entire lot over depending on how I feel. He says that the diaphragm doesn't come off on it's own. It is attached to a yellow tube that goes inside the rest of the unit. Is there any way I (he) can remove this easily?


You should see a big difference when it works at least 3 ponies.

That doesn't sound a lot to me. :confused:


Did you align the distributor rotation back up? Have you had the battery disconnected? Maybe you blew too hard and broke the diagram.

No. To all three. I blew very gently.


I’d remove the pipe that attaches to it, and block it off till you get a good diaphragm.

Make the diaphragm airtight, right?


The Speedo cable comes through the other side of the bay. That would be the throttle cable your arrow points to.

Make sense what with going to the carburettor and all ;)


If the oil inside your engine is clean, any new leak will be the same colour if you cleaned the old stuff off well.

It was roughly wiped with a very oily cloth. Might see if I can clean it up a bit more tomorrow.


Speaking of which... whats the best way to clean the engine bay up? Degreaser and a low powered hose? What about the greasy run-off? Should I clean it on a hill just before a drain?
 
Whether or not it is, I'll be getting it anyway. Will possibly change the entire lot over depending on how I feel. He says that the diaphragm doesn't come off on it's own. It is attached to a yellow tube that goes inside the rest of the unit. Is there any way I (he) can remove this easily?

The 'yellow tube' is actually a plastic link that fits over a ball-shaped pin. Use a thin screwdriver to pry the split end open so that it pops off the pin. They are such a common failure that it's probably worth buying a brand-new vacuum advance capsule. About 10-20 pounds I expect.

Speaking of which... whats the best way to clean the engine bay up? Degreaser and a low powered hose? What about the greasy run-off? Should I clean it on a hill just before a drain?

Aerosol can degreaser, water soluble, and a brush - you have to put in the elbow-grease scrubbing to get the results. As for the greasy (water-dissolved) runoff - oh yes - you can't clean the car on the ground. Anywhere. It has to be placed in a reclamation booth at the Oil Treatment Plant. Otherwise, mercury levels in Scottish kippers increase and dolphins in the arctic circle die. You should know that ;)

I thought your original post had rather excitable language (and what about the tags on this thread...?) but Louie really does take the cake for "My little pipe falls off, and Dunc snapped his trying to slip it over." Proof that size does matter, at least to some extent. Just an unfortunate juxtaposition of names and verb subjects there...!

-Alex
 
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Thanks :)

edit - the pipe to the carb is now all blocked up. Just waiting for the replacement distributor to arrive, then I can change them over.
 
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New distributor has arrived, plus 3 working spark plug leads, a new ignition module, and new distributor cap (with 2 even smaller graphite contacts than my original one! :( )......and an equally broken diaphragm. :(


Now, where'd I put that link to the place you can buy spares from....?


There is a severe lack of power, the normal speedy run to and from work down the motorway was definitely slower, my little Uno had problems getting up hills (down into forth) and it's still got cack acceleration.
At least the engine bay doesn't have new oil in! :D

However, its booked in for a full service next weekend. Will get them to check the timings, adjust my handbrake (Louie - it only does 5 clicks, so I have no idea what your 13 or 17 was about!?!) and all the other stuff they usually check. Can anyone think of anything that I should get them to specially look at?

Also, here is a picture of the distributor and O ring that arrived today (the O ring is in the same condition as my old one was) just so people can use it as a reference in the future:

oldring1small.jpg



oldring2small.jpg
 
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New vacumm advance thingy ordered from shop4parts for a grand total of £20.25

Not bad I think. :)
 
Louis, I think I love you! :D
(also, your inbox was full when I tried to PM you)

So the new diaphragm arrived today. Top marks to shop4parts, next day delivery :)
Put it on, very easily. If changing the O ring is half a spanner, changing the diaphragm is a quarter spanner job. Utter piece of p1ss that I genuinely could have done it with my eyes closed. The only trouble I had was screwing the bugger back on. I put the top screw back in first which is in an oval shaped hole, but I should have done the bottom ones first. Other than that, it was all very plain sailing.

Here are the mandatory pics:

Old one after I had unscrewed it, then remembered I had to take pics for you all, so I screwed it back on! (well.. one of the screws ;) ):
diaphragm1small.jpg


This is how the pipe is connected on via the ball joint (plastic pipe goes to the left and the balls pops out on the right. I had to give it a firm push back on to the new one though, was worried I'd snap it! :D ):
diaphragm2small.jpg


I then realised that the above pic was a bit dark, so I took one with a flash:
diaphragm3small.jpg


Here is the old diaphragm on the pavement, you can clearly see where the ball goes on:
diaphragm4small.jpg


I also took this moment to give the old oil a clean off to make the engine look a bit tidier.

New one screwed on:
diaphragm5small.jpg


Pipe connected up:
diaphragm6small.jpg


..and done.

I took it up the bypass twice to get some idea of how it was running, and the answer is beautifully. It really is back to its' nippy old self - no juddering and slow acceleration. Will be good to see how it performs after the full service on Saturday, as well as the way to work tomorrow! The petrol consumption has definitely been hit down a notch whilst the tube was disconnected though. I have less than I usually do at this point in the week.

It does seem to be idling a little higher than it used to however. Any ideas what might be causing this anyone?


AlexGS or Jai - can you rename this thread "The day I changed my O ring and diaphragm" please? Just to make it a bit easier for anyone looking for the same in the future. Thanks! :)
 
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I was about to say: "it isnt on the wrong way... its always been that way on every Uno ive seen (non Turbo! ;) )"

Your parcel should arrive tomorrow. :)
There will be pictures, oh yes :D

Forgot to mention, as said before, you really should not be able to blow down the diaphragm. Having never had a working one to blow down, I didn't know what to expect, but there really is NO give in blowing it. Do NOT blow hard AT ALL. Blow as gently as you can and you will see what I mean.
 
Good work uCof (y)

Your engine's STILL not clean, though. My cornflakes would be covered in dust and oil. I don't think you've spent four hours, three large spraycans of degreaser, and several toothbrushes yet. Nor do I think you've nicked the stainless steel polishing powder from the kitchen and gone over the alloy with a floor scrubbing brush. :p

If you haven't already, you do need the timing to be re-checked, unless it was set in the correct way before, which is: vacuum advance disconnected, engine idle speed around 800RPM, use a timing light triggered by cylinder 1 to illuminate the notch on the flywheel through the bellhousing window, adjust distributor to align illuminated notch with 5 degree line scribed on window.

-Alex
 
Good work uCof (y)

Your engine's STILL not clean, though. My cornflakes would be covered in dust and oil. I don't think you've spent four hours, three large spraycans of degreaser, and several toothbrushes yet. Nor do I think you've nicked the stainless steel polishing powder from the kitchen and gone over the alloy with a floor scrubbing brush. :p

If you haven't already, you do need the timing to be re-checked, unless it was set in the correct way before, which is: vacuum advance disconnected, engine idle speed around 800RPM, use a timing light triggered by cylinder 1 to illuminate the notch on the flywheel through the bellhousing window, adjust distributor to align illuminated notch with 5 degree line scribed on window.

-Alex

You'd be correct there. I have done any of the toothbrushing, degreasing and polishing ;)

regarding the timing... "lolwut?!" - I'll leave it to the garage to do on Saturday ;)



Drove car 30 miles down the motorway to work today. Was beautiful :D She is back.


oh..and thanks for changing the title :)
 
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