Welch plug

[Keith83]

Helo.
I have a uno fire 1100.
I put bigger pistons, new oil pump, new water pump almost everything new on the engine. But I have 1 problem. The welch plug between engine and gearbox keeps popping out whenever I push it a bit. It happend 3 times now and to remove a engine 3 times in a month..... no comment lol. Please help anyone. What can be the cause???

 

[varesecrazy]

Helo.
I have a uno fire 1100.
I put bigger pistons, new oil pump, new water pump almost everything new on the engine. But I have 1 problem. The welch plug between engine and gearbox keeps popping out whenever I push it a bit. It happend 3 times now and to remove a engine 3 times in a month..... no comment lol. Please help anyone. What can be the cause???

Hi,
you must have a blocked / blanked breather,

(the pistons work like a pump, and the pressure waves are what are moving the plugs..,)

Charlie

 

[Keith83]

Hi Charlie.
Thanx but how do I go about fixing that and where/what is it the breather thats blocked lol. Dont know where to look?

Keith

 

[portland_bill]

Clarify please. Is this in the coolant gallery, or the oil gallery? I'm guessing the oil gallery.

Engine breather issues will cause crankcase pressure, but this will normally escape through normal oil seals or blow the dipstick out. The breather is the little pipe from the cam cover to the air cleaner. Remove this from the cam cover. Inside the end should be a small spiral gauze filter. Give it a scrub with degreaser and an old toothbrush, and check the whole pipe is clear.

If this is an oil gallery issue, it would point at the pressure relief valve in the pump being stuck shut. A tiny bit of debris will cause this. It looks like the relief valve is accessible once the sump is off. Compress the spring and prise out the retainer plate. Spring and plunger should then come out, although might be difficult if it is jammed. Turning the engine by hand might pop it out, but careful not to lose anything.

I'd expect the oil pressure switch to suffer, is it leaking?

You're not re-using a welch plug are you? They do need to be tight.

 

[Keith83]

Hi Potland Bill. Im planning to take out the engine tomorrow to put a new plug and while its out ill check if anything is jammed. I did replaced the old plug with a new one. I did replace the oil plug aswell as the oil light keeps flickering on low refs when engine is hot. It still flickers though. I did replace the oil with a thicker oil and it seemes to help a bit. The oil light dies when I drive at about 2000rpm. The engin was reasonly done. New pistons(bigger), bigends and mains, oil pump, water pump, head was done. Almost every is new on the engine.

Maybe all this info will help.
Thanx

Keith

 

[portland_bill]

So it is the oilway plug?

Strange that you have low oil pressure warning, but enough pressure to blow the plug out of the gallery. Perhaps the excess pressure has damaged the switch.

With all that work, if checking the pressure relief valve does not find the issue, I'd be wanting to put a pressure gauge onto the switch position to read exactly what pressure there is. Some garages may still have such kit, if they can find it.

Thicker oil is not really a good idea. Small oilways do not like thicker oil, and can lead to the oil not getting around where it should. 10/40 should be fine I think for that engine.

It is possible to fit the head gasket upside down, which blocks the oil feed to the camshaft. As well as starving the cam and followers, this might cause the pressure to eject the plug. Take the cam cover off and see if there is oil being delivered to the spray bar.

 

[varesecrazy]

So it is the oilway plug?

Strange that you have low oil pressure warning, but enough pressure to blow the plug out of the gallery. Perhaps the excess pressure has damaged the switch.

With all that work, if checking the pressure relief valve does not find the issue, I'd be wanting to put a pressure gauge onto the switch position to read exactly what pressure there is. Some garages may still have such kit, if they can find it.

Thicker oil is not really a good idea. Small oilways do not like thicker oil, and can lead to the oil not getting around where it should. 10/40 should be fine I think for that engine.

It is possible to fit the head gasket upside down, which blocks the oil feed to the camshaft. As well as starving the cam and followers, this might cause the pressure to eject the plug. Take the cam cover off and see if there is oil being delivered to the spray bar.

there is a TAB on the gasket..so orientation can still be checked once assembled


Re: Punto 1,2 8v engine won't start after breakdown on highway
Quote Originally Posted by Mathias View Post
Is there an easy way to decide whether that have happened or not, without have to take the head off?
Can I check oil channel another way?

The head gasket has a rectangular tab approx 10x20 mm that sticks out. When it's on the right way the tab sticks out near the dipstick.