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Sun Jun 10, 2012 4:34 am

None of the cylinders have any compression, the gauge is working I've checked.
My timing is right, I have a spark & fuel. :shock:

Sun Jun 10, 2012 4:40 am

Adjust valves.

Sun Jun 10, 2012 4:43 am

I have hydraulic tappets, I've got the rocker cover off, I've adjusted them on cylinder No.1 There is a small amount of play & I can see the valves opening & closing as the engine turns over.
:shock:

Sun Jun 10, 2012 4:45 am

Loose head?

Sun Jun 10, 2012 4:50 am

With hydraulics if you tighten them up over what they were set at, say from 1 turn to 1 1/2 turns they will hang open initially and you will have zero compression. Once you get it started they should quickly self adjust.

You did just use your fingers to turn the screws in so you could feel the point of contact didn't you. You may miss the point of contact if you just take a big screwdriver and go at it and as a result your valves will end up being set so tight they will never close.

Sun Jun 10, 2012 4:56 am

bsairhead wrote: Loose head?
Not a loose head, cos I torqued them down well.

Sun Jun 10, 2012 4:57 am

Wildthings wrote: With hydraulics if you tighten them up over what they were set at, say from 1 turn to 1 1/2 turns they will hang open initially and you will have zero compression. Once you get it started they should quickly self adjust.

You did just use your fingers to turn the screws in so you could feel the point of contact didn't you. You may miss the point of contact if you just take a big screwdriver and go at it and as a result your valves will end up being set so tight they will never close.
I might have on No1 cylinder but not the others, what can I do now? :shock:

Sun Jun 10, 2012 5:05 am

Forgot to say my bus is a 1979 with a 2.0L Type 4 motor its FI with hydraulic lifters.

Sun Jun 10, 2012 5:17 am

chrisradioman wrote: Wildthings wrote: With hydraulics if you tighten them up over what they were set at, say from 1 turn to 1 1/2 turns they will hang open initially and you will have zero compression. Once you get it started they should quickly self adjust.

You did just use your fingers to turn the screws in so you could feel the point of contact didn't you. You may miss the point of contact if you just take a big screwdriver and go at it and as a result your valves will end up being set so tight they will never close.
I might have on No1 cylinder but not the others, what can I do now? :shock:

Just go back and reset them keeping in mind that the point of contact can be quite subtle. Also do not push in hard on the bottom of the rocker while doing the adjustment as this may partially collapse a not fully pumped up lifter and throw the adjustment off

The book says 2 turns of preload, while many swear by less. I would recommend you not go below 1 turn.

Sun Jun 10, 2012 5:23 am

Shall I turn the engine over first to build the compression?
:oops:

Sun Jun 10, 2012 5:30 am

chrisradioman wrote: Shall I turn the engine over first to build the compression?
:oops:

You don't not need compression to adjust the valves. With hydraulics the lifters can be properly adjusted hot or cold, with or without being 100% pumped up.

How much did you back the adjusters off when you first went in there? Good idea to keep track of this info so you will know if any adverse wear is happening. Also take a look at your adjusting screws after you get this set correctly. They should pretty much all have a similar number of threads showing.

Sun Jun 10, 2012 8:39 am

chrisradioman wrote: bsairhead wrote: Loose head?
Not a loose head, cos I torqued them down well.
How did you get to the upper nuts?, is the engine out?

Sun Jun 10, 2012 8:58 am

Wildthings wrote: chrisradioman wrote: Shall I turn the engine over first to build the compression?
:oops:

You don't not need compression to adjust the valves. With hydraulics the lifters can be properly adjusted hot or cold, with or without being 100% pumped up.

How much did you back the adjusters off when you first went in there? Good idea to keep track of this info so you will know if any adverse wear is happening. Also take a look at your adjusting screws after you get this set correctly. They should pretty much all have a similar number of threads showing.

I've now done what you said, I think quite a few of them were out a lot, all the lengths look the same now.

This is what I done, set the engine to TDC, slackened off the adjusters, then tightened by hand until they just touched the valve stem, then I wound it in one complete turn.
Turned the engine 90deg anti-clockwise & repeated on No. 2.
Then I repeated the process on No.3 & 4.
The bus still won't start but it sounds better when turning over. :D

Sun Jun 10, 2012 8:59 am

busdaddy wrote: chrisradioman wrote: bsairhead wrote: Loose head?
Not a loose head, cos I torqued them down well.
How did you get to the upper nuts?, is the engine out?
The engine was out I've done a full rebuild. Its back in the bus now. :D

Sun Jun 10, 2012 9:05 am

Did you test compression this way?

Remove all spark plugs
screw the compression gauge in #1
Hold the throttle open
With the starter crank the engine through 3 to 4 full cycles RRRrR RRRrR RRRrR RRRrR
Read the compression

Sun Jun 10, 2012 9:06 am

I did but I now need to do it again. :D

Sun Jun 10, 2012 9:30 am

Has the engine been run since the rebuild? Did you oil the rings during assembly?

Sun Jun 10, 2012 9:31 am

busdaddy wrote: Has the engine been run since the rebuild? Did you oil the rings during assembly?
The engine hasn't been run yet, I used assembly lube on everything inc the rings. :)

Sun Jun 10, 2012 9:49 am

Don't expect any reliable compression numbers until after the rings have seated, run it a while first.

Sun Jun 10, 2012 10:07 am

Quote: None of the cylinders have any compression

I read the word any to mean -0- as in nada, none. If the OP meant otherwise please correct this misnomer. A new engine will have lots of compression.