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Tips
Tips

Valve Oil Seals

OP
6

65_BRG_Sprite

Jedi Warrior
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'65 1098, has not run but few miles in the last 4-5 years. In the past it would produce a little smoke and oily odor. Started it the other day and it blueish smoke billowed. Pulled plugs and they are a very nasty black and oily. Compression on all cylinders is 175. Leads me to believe dried up oil seals. Have youtubed it and watched several videos and as usual give them partial credibility. I intend to replace the seals with the head in situ, I see NAPA has compressing lever tool for $15 that hopefully will do the job. Any words of wisdom and\or cautions before I dig into this project?
 
Plug Pic 1.jpeg
Plug Pic 2.jpeg
 
I think the smoke will be more like black if too rich. But worth a try first certainly.
 
If this condition is on every plug equally, mixture seems more likely the culprit. Per the Moss catalog, your valve seals are o-rings. These act more as an umbrella than a seal, so even if they are hardened they would work as designed if in place.
Bob
 
I'd agree that mixture is a likely culprit, but to me at least, blue smoke means oil.

Simple enough to fix the mixture first, though, and see if that cures it. Also, it would be a good idea to clean or replace the plugs.
 
Thank you, yes the plugs sprayed w/carb cleaner. Had to run out for a new brass brush and by the time I got back I had to go to my primary job- labrador retriever valet. First thing tomorrow though.
Stay warm out there, winter finally settling to central Ohio.
 
In case you decide to work on your valve seals..........
I recently posted an article on the Moss news letter concerning valve compressors.
It is a home made valve compressor.
I don't know how different yours is than mine (I have an MGTD - 53) but if your valves have two springs each, finding a spring compressor to compress both springs is difficult. Many only grab one spring.
My compressor (invention - lol) compresses both springs together). It allows upper valve work without removing the head.

06/25/23Valve Spring Compressor
This Issues Tech Tip Is From Russ V
Below you will find a few pictures for a tool I had to make in order to do some work on my valve springs and valve seals on my 1953 MGTD. (valve seals were shot causing a lot of oil to get into the cylinders). It also helps a lot to be able to change valve springs without removing the head!
There is also a problem uncovered with many engines that have been worked on by people that are not familiar with XPAG engines, the valve seals get installed incorrectly below the spring washer (instead of above the washer and below the cotters causing a lot of oil to pass down the valve into the cylinder!
This tool allows the valve springs and seals to be worked on or replaced WITHOUT removing the head!!!!
It is a valve spring compressor.
There are a few valve spring compressors on the market (and I have a few) but none of them worked. The XPAG engine uses two springs for each valve. Some of the spring compressors available work on some cars with one spring (by grabbing onto the spring and using a dial to compress the spring) but it does not reach the internal spring on an XPAG engine so they cannot work. There are also a few compressors available but they require the head to be removed (not everyone is comfortable doing.
So I made a basic spring compressor.
VERY easy to make
I used a standard pry-bar / nail remover available at any hardware store or Home Depot.
First picture is a "BEFORE". This is a standard pry bar / nail remover.
On one end I used a grinder to open up the pry end (where a nail usually goes) so that it will push down on the spring washer above the spring and allow the top of the valve (with cotters and seal) to pass through it.
I then drilled a 3/8" hole into the oblong hole to make room for the rocker panel bolt to pass through it and screw into the head.
The next picture shows the end that is ground down with a grinder to make room for the top of the valve (and seal and cotter) to pass through while holding down the spring washer. It also shows the 3/8" hole drilled out for the rocker panel bolt.
VERY simple tool. Easy to make. Worked great!
Of course, each piston should be brought to TDC so that the valve does not fall into the cylinder. Ensuring the valve does not fall can be done by applying air pressure to the cylinder via the spark plug hole OR push some vinyl rope into the spark plug hole to ensure the valve stays in a closed position. (I don't use cotton rope it can leave lint in the cylinder and it is hard to push in)
Basically, after removing the valve cover and the rocker panel, each spring can be compressed by passing the larger rocker panel bolt (320-530) through the hole in the tool and screwing it into the head where it was removed from. The "ground end" of the tool is placed above the valve and the valve spring washer. Tightening or loosening the rocker panel bolt comes in handy in order to get the best leverage (and adjust for any curvature that the pry bar has). Pushing up on the longer end of the tool compresses the springs. That gives you great leverage to be able to compress the spring, remove the cotters, remove the valve seal, and remove the springs. The tops of two valves can be worked on from each of the positions for the rocker panel holes. To re-assemble simply reverse the procedure.
I have tried many times to do this with other valve spring compressors but each was a nightmare.
I hope this helps someone.
1706652676218.png
 
I should have taken pictures while "in use" to show how easy it works.
The real advantage is when compressing the springs when there are TWO of them on the valve (typical of older MG engines).
Most spring compressors grab ONE spring (the outside one.... but not the internal one). Other compressors require the head to be removed.
The next time I work on the valves and remove the valve cover I will take pictures.
I should have also stated that the rocker assembly has to be removed (which is very easy) which is MUCH easier than removing the head
 
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