Chev 216 loose piston pin - which one ?

[Mike Kelly]

Hi

I have been working on my cab 11 C8 , a refurbishment and a general cleanup with the club rego in mind for later in the year .

Anyway the first job is to fix the annoying rattle of a loose piston pin . At this point I don't know which piston is making the noise , the noise has always been there since I got the C8 running . The knock is only evident after revving the engine and then listening as it idles , the noise is not there when above idle speeds .

I am doing this on my own, I know that I can remove a spark plug lead and listen for a change in the knock - but with only one pair of hands . Is there an easier method ?

I have removed the engine covers, a major job in itself

Another query. Does anyone know the dimensions of the valve guides for a 1940 216 engine ? The valve stem diameter and the length of the guides ? I think the 1941 engines are slightly different Thanks

[Keith Webb]

Don't have an answer for you Mike but great to hear we'll be seeing the C8 on the road again!

[hrpearce]

Mike, with the engine covers off do you have enough access to use a long screw driver to listen to the side of each cylinder. That is what Dad used to do on Bedford engines.

[Lynn Eades]

Hi Mike, you should be able to short it out at idle (it will only be audible at idle) (just use a screwdriver from plug lead to head)
If it is a timing gear noise, it won't short out.

[Phil Waterman]

Hi Mike

Here is a video of hunting down a noise inside the engine as suggested. I had a similar engine noise while the engine was still on the test stand. In my case it was not piston pin but only a miss-adjusted lower connecting rod. Remeasured and reshimmed noise when away.

https://www.youtube.com/watch?v=cAjy8LjiexQ

Cheers Phil

[Mike Kelly]

Originally Posted by Phil Waterman

Hi Mike

Here is a video of hunting down a noise inside the engine as suggested. I had a similar engine noise while the engine was still on the test stand. In my case it was not piston pin but only a miss-adjusted lower connecting rod. Remeasured and reshimmed noise when away.

https://www.youtube.com/watch?v=cAjy8LjiexQ

Cheers Phil

Ok nice videos , I took the time to look through them all at here the library. The slow wipers on the HUP are mesmurising .... they would put me to sleep as I was driving along . My C8 has the same sleepy wipers .. has anyone fitted a vacuum tank yet ?

I will ask my neighbour down the road to help me out with the diagnosing of the piston pin noise in the C8 engine .

The valve guides have a .342 " bore and a OD of 9/16" . There are cheap modern generic guides available with a .342" bore but they have a OD of 1/2" EGGE parts in USA have the correct guides for 2.60 $ US each but the postage is a killer .

[Mike Kelly]

Originally Posted by hrpearce

Mike, with the engine covers off do you have enough access to use a long screw driver to listen to the side of each cylinder. That is what Dad used to do on Bedford engines.

Robert you need to be a skilled circus acrobatic act in order to work on the engine in the cab 11 ...... or 12 . The mechano set bolt down engine covers in the cab 11 are a nightmare to remove

[Mike Kelly]

Been fiddling and the fuel pump decided not to work, as I removed the fuel bowl from it, a nasty smell of stale petrol appeared . After investigation, the pump was gunked up with a fine brown gunk. Modern petrol is the culprit here , it leaves a brown film on fuel components , it can block jets and cause trouble in petrol tanks .

re: the valve guides , American auto parts in Ballarat have the generic early chevy guides, over 3" long , for $5 each. I will machine them to length .

I also got a aluminium timing gear to fit , I've seen the old fibre gears strip teeth too often .

[Mike Kelly]

Well, the engine has had a run, warmed up and had a listen, could not hear anything out of order . The mystery noise comes and goes .

The water pump bearing is growly, this is a problem Ive always had with these engines. You buy a old stock kit, made 60 years ago, and the bearing grease has dried out , you install the kit and give it a try , the bearing sounds horrible . You buy a modern bearing , made in Taiwan, it lasts 3 months and is stuffed and wobbly and the pump leaks .

What do you do ? The bearing is a sealed unit. I will dismantle one and see if it is possible to re lube it somehow ?

The 75 year old radiator is also leaky ..looking rather sad . May have to do the recore .... save some pennies .

[maple_leaf_eh]

Originally Posted by Mike Kelly

Been fiddling and the fuel pump decided not to work, as I removed the fuel bowl from it, a nasty smell of stale petrol appeared . After investigation, the pump was gunked up with a fine brown gunk. Modern petrol is the culprit here , it leaves a brown film on fuel components , it can block jets and cause trouble in petrol tanks .

re: the valve guides , American auto parts in Ballarat have the generic early chevy guides, over 3" long , for $5 each. I will machine them to length .

I also got a aluminium timing gear to fit , I've seen the old fibre gears strip teeth too often .

One suggestion I learned this summer was to pour in a measure of fuel stabilizer with each fill-up of an HMV. The stabilizer is sold in Canada to small engine users at the change of seasons. With a dose in the tank, snowblowers, lawn mowers and rototillers should be ready for the next year with fewer fuel problems. The stabilizer will always be in the tank and lines, and as a combustable it can't hurt.