Joined: Mar 2015 Posts: 5,465 Threads: 231
Reputation:
67
Location: Scotchland
03-06-2021, 04:53 PM
(This post was last modified: 03-06-2021, 04:56 PM by Ruairidh Dunford.)
As Nick says above, your engine is too far advanced, Electronic ignitions like the one you have will take a lot of retard and still pick up nicely.
Set tick over at roughly 1000rpm and rotate the distributor, slowly, clockwise (looking down on it) until you have a quiet and smooth engine, check for nice pick-up. If flat, rotate clockwise in minute increments, checking pick up each time. They are much more sensitive than traditional units but work incredibly well once correct.
You will need to reset you inlet tappet gaps to 0.006" and your exhausts at 0.008".
p.s. I don't like the noise in the film of the valves moving up and down by hand, something is binding...
Joined: Aug 2018 Posts: 281 Threads: 38
Reputation:
1
p.s. I don't like the noise in the film of the valves moving up and down by hand, something is binding...
Exactly, this is another issue with the engine, will do the timing tomorrow, neighbors getting a bit cheesed off with the noise & me haring up and down the road !!! :-)
Joined: Mar 2015 Posts: 5,465 Threads: 231
Reputation:
67
Location: Scotchland
Is the information above the p.s. of use to you at all?
Joined: Aug 2018 Posts: 281 Threads: 38
Reputation:
1
Yes, will be looking at resetting the timing, and take another look at the valve clearances, but tomorrow.
Joined: Aug 2017 Posts: 2,418 Threads: 33
Reputation:
37
Location: Deepest Frogland 30960
Car type: 1933 RP Standard Saloon
A classic error when rebuilding is putting the wrong length sump bolt in the hole directly below the flywheel...
Joined: Aug 2017 Posts: 2,418 Threads: 33
Reputation:
37
Location: Deepest Frogland 30960
Car type: 1933 RP Standard Saloon
03-06-2021, 07:53 PM
(This post was last modified: 03-06-2021, 07:55 PM by Reckless Rat.)
Yes and/or no, depending on the length of the bolt...it's not difficult to see whether there is interference or not.
Joined: Aug 2017 Posts: 783 Threads: 26
Reputation:
8
Location: On a hill in Wiltshire
Engine sounds like an A7 engine. They don't approach sewing-machine smoothness.
You hear the rumble made by over-advance best if you blip the throttle a little.
Also, a loose flywheel shows up better with a "blip".
If you had a video of the engine with the throttle being snapped open a bit, it would make it easier to diagnose.
The squeaky noise is a big no-no. That needs sorting before anything else.
The centre rear sump bolt may just be catching the flywheel, causing the squeak. Back it off 1/4 turn, and try turning the engine by hand, see if the noise goes away.
Otherwise? Tight valve guides - doesn't look like it. Cam front bearing retaining bolt too long? Don't think it would sound like that.
Top fan pulley bearing running dry? Maybe. Unexpected item in the flywheel housing area? Maybe.
Un-lubricated areas anywhere in the crankcase or block? Unlikely, given your problem of excessive fluids in the sump.
Joined: Aug 2017 Posts: 622 Threads: 19
Reputation:
10
Location: Hampshire UK
Hi flywheel
I have had a listen to the videos. Sounds like an A7 engine to me, I think I would have to hear it in person to diagnose much more. Only exception is the odd squealing. My own engine has a late Ruby HC head with a 2 bearing bottom end, and this combination definitely resulted in a harsher sounding engine - something other forum contributors have noted over the years.
The main distinction with engine noises is whether they are related to the engine load/throttle opening or happen just as a consequence of rotation almost regardless of load.
Load related would be big and little end bearings, pistons and combustion. Over advance will cause harsh running which will diminish noticeably as you back off the throttle and thereby reduce cylinder peak pressure. With modern fuel octane it will never pink, but given way too much advance it can get to the point of a diesel-like rattle. In my experience the 2000 to 2300 RPM range is the severest test, which annoyingly coincides with about 30 mph in top gear. One option is accelerate through this range, but this is easier in a light special than (say) a saloon climbing a gradient.
Non load related would be camshaft, valve gear, dynamo, distributor etc. Sometimes a stethoscope or large screwdriver as a conductive listening device can pinpoint the source. If something is binding you should feel it on the starting handle, maybe easier with the plugs out.
I have dug out my data on the standard ignition advance for the late Ruby. The static advance is about 5 crank degrees, and the additional centrifugal advance climbs linearly from nothing below about 900 engine RPM to 16 degrees maximum at 3200 RPM and above, i.e. a rate of 7 degrees per 1000 RPM. I don't have any data for the electronic distributor. All I can suggest is setting the advance by trial and error for best performance at the RPM range you use most, using the least you can get away with without letting power drop too much. The advance at idle is not separately adjustable, so you will have to accept what it is.
