Timing off by 30 Degrees...

[Marc123]

I have what I 'Thought' was a 265 cubic inch flathead 6 with a 25 1/4" head and the Spitfire logo on it.

The left front ID stamping flat is BLANK.

There are no other tags on the engine.

The block casting is dated 2-17-1953.

It's installed in a 3 wheel loader built before they invented articulated loaders.

It's a Scoopmobile Model H.

I've had it for about 20 years and just putter around the yard with it, it's never ran quite right, but well enough.

The project I needed to do was always much more important than turning the loader into a project.

That finally happened. It started with the water pump.

Scope creep kicked in and I'm surprised it ever ran at all...

Fixing a few dents and small leaks in the oil pan revealed a lot of hidden corrosion, thin spots and a lot of brass that

all fell apart as soon as I hit it with a torch.

The starter failed. What I thought was a ballast resistor for the ignition was actually for the first of two solenoids in the

starter that was a 6 volt hold-over from a prior 12v conversion.

So a rewired EVERYTHING.

I couldn't get it to run, so I rebuilt the Carb.

I still couldn't get it to run. 

I cranked on it too much, got fuel in the crankcase and had a huge explosion, I didn't know that was even possible.

I blew out the gaskets on the side covers for the lifters & valves.

I couldn't seem to find the right parts for the distributor, so I replaced the guts with a Hot-Spark ignition module.

There was what I presumed to be a timing mark someone made on the front pulley with a chisel.

There is a rusty chunk of wire bolted to the timing chain pulley cover.

I put an indicator on the #6 piston and the center of the dead zone between when the piston is coming up and before it

starts to go back down lines up dead on with the mark and wire.

I sprung for an electronic advance timing light and once I FINALLY got it running again, Cylinder #1 has to fire about 30 Deg. before that TDC mark.

 

That 30 Degree number probably means something, but I don't know what I'm missing.

It still does not run well, but I'm at a loss as to what to do about it.

No idea if the Carb with an adjustable jet is set correctly or not.

 

Any ideas?

 

Thanks

Marc

 

[lostviking]

Take the plug out of #1. Take the cover of the lifters. Put your finger over the #1 plug hole and rotate until it's pushing air out...and the lifters are both on the base circle of the cam. Unless you want to take the head off, that's probably the best you can do to getting it to TDC. Figure out if that mark is anywhere close.

 

Personally, I'd take the head off and indicate TDC, then mark it again so I know it's in the right location.

 

You can't assume that someone else put a mark in the right place. Obviously, something is not marked correctly...I doubt the engine would run at all if it was 30 deg's off.

 

I'm married, so I've been wrong before.

[Marc123]

On this particular engine there is a plug, as in 'Pipe' Plug over the #6 piston.

I pulled it out and used a rod and dial indicator to find what I assume ( I'm married too..) is Top Dead Center of the exhaust stroke.

That is Supposed to be TDC on the firing stroke of Cylinder #1.

There is hardly any movement of the pistons for a fair bit of rotation around TDC.

I split the difference between when I stopped feeling it coming up and when I could first started to feel it go down.

I Presumed that was TDC.

Is TDC considered one of those other points rather than the middle?

 

I did that 3 times without looking at the existing mark and tainting what I was feeling.

They all came out dead on that mark.

 

The valve stems and tappets are accessible on the side of this engine.

I have the covers off.

I didn't measure the Exact clearance but a 0.010 feeler gauge slipped under both valve stems on #6 when it was aligned with the mark.

I rotated the crank 3 more turns and the feeler would slip under the valve stems on Cylinder #1.

 

I 'Think' that proves the timing chain has not jumped a cog and the cam and crank are in sync ???

 

The plug mentioned on Cylinder #6 had a fair bit of carbon on it and a bit I had to break off when inserting the rod to feel the piston position.

I have no idea if the Carburetor is set correctly or if I messed up the rebuild. 

The carb is a Zenith 228.

The idle mixture screw is tight, then backed out 1 1/2 turns.

The Main jet is also adjustable, it was tight then opened up 4 1/2 turns.

I messed with them a bit but nothing got better, I could only make it worse.

 

Could a really BAD Fuel/Air ratio or a bunch of crud in the cylinders slow the flame wave front in some way making the extreme advance necessary?

 

The mechanical advance on the distributor had one 'light' spring under a bit of tension at rest and a heavy one that didn't even make contact until

about half way out.

I made two matching ones from springs I scrounged up from who knows where, based on no real specs.

The only springs I could buy were off eBay, they had no real specs and the markings on the package when I got them said 'Ford'.

Neither set made any difference.

Here are the originals, the graph paper is 1/4".

 

 

I am Assuming.. all that is irrelevant and could mess up the amount of advance at different RPMs, but not cause this.

I figure the timing light is the final authority on when that plug fires.

Is that a bad assumption??

 

I engine manual I have lists the mechanical advance from 0 to 10 degrees at various "Distributor RPM" values.

Is the 'Distributor RPM' going to be 1/2 or 1/4 the 'Engine' RPM?

[maok]

You need to confirm when checking  the TDC of #6 if its firing or exhaust stroke, you cant assume its exhaust stroke just because its #6 you are checking. If the distributor was installed correctly and the rotor points to #1 plug lead, therefore #1 piston is at TDC'ish or points to #6 lead then #6 is at TDC'ish. If you can't rely on the distributor being installed correctly then you need to confirm with the valve positions by removing the side plates to check. If #1 TDC then both valves will be closed completely, same applies to #6.

[Tooljunkie]

Finding tdc requires you to turn engine clockwise, mark pulley when wire tops out, then proceed past then rotate crank counterclockwise and make another mark. Split difference. 
that is tdc. 
 

[Tooljunkie]

Crankshaft rotates 2 times for one revolution of distributor. 
and the 2 different springs in distributor are correct. For progressive timing advance. 
no mention of vacuum advance, common in industrial engines. 
set timing for 15-18 degrees advance at 1800 rpms. I think thats about all the timing it needs. 
 

 

[Merle Coggins]

Are you saying it needs to be set at 30 degrees advance in order for it to even run? That would be odd, unless your marker is off by that much. As Tooljunkie alluded to, the only way to properly find TDC is with a piston stop set to stop the piston before it reaches the top of it's stroke. You'd rotate the crank until the piston comes up against the stop. Then mark your pulley, Rotate the crank the opposite direction until the piston comes up against the stop again. Mark your pulley again at this point. Half way between the two marks will be TDC. 

You could probably achieve similar results with a dial indicator, or some other way to measure the piston height as you turn the crankshaft. Just stop at the exact same height in both directions. 

 

Have you don't a compression test on this engine? Low compression on one or more holes will make an engine run pretty rough. 

 

Is this a Zenith updraft carb? I don't know a lot about Zenith carbs, but I've seen a few on older equipment. 

 

Can you share some pictures of this machine? Does it look something like this? (image pulled from the internet)

[Marc123]

Thanks everyone.

That's a lot to reply to.

I did check the valve positions and verified when Cyls #6 & #1 where on the firing stroke.

I've had the distributor off and cleaned and lubed it in addition to converting it to a Hot Spark solid state

ignition along with their suggested ballast resistor and new Bosch coil.

The Hot Spark docs say "The timing may need to be adjusted by as much as 30 Degrees" after the conversion.

I am assuming that would be due to mechanical and possibly capacitance differences, and the 'Adjustment' would be

to get get the plugs to fire at the Correct position RATHER than changing the actual firing position by 30 Degrees.

 

That's good to know about the springs.

None of my docs cover my particular distributor, a Chrysler "Auto Lite" "Solar Spark Ignition" IAD 4040-1.

 

I'll have to pick up a compression tester, I almost bought one when I picked up the electronic advance timing light, but didn't.

The wife was with me and was already getting annoyed at all the additional stuff I kept finding and adding to the cart ;-).

 

My projects seem to have a bad tendency for me to put a lot of time into fixing them up and THEN finding or causing a huge show-stopper.

 

Like spending a month installing a New 22hp engine on our Chipper/Shredder along with all necessary modifications to make it fit and fabricating

an appropriate pulley for the engine.

We used it for about 3 hours and it worked like a charm. Until... 

I was using a heavy machete to split off branches and stuff coming off at odd angles to fit some stuff in the chipper side.

I threw the wrong handful of stuff into the chipper and the machete busted one of the blades.

I can't get blades for it anymore.

They are odd shaped and I'm not confident enough that I could fabricate and harden the CORRECT alloy in order to make new ones. 

I found a very common style and size of blade. Modifying the 5/8" mild steel chipper blade plate to accept them is a safer bet and a project for the winter.

 

Or a month spent fixing up my 1958 Fordson Major Diesel tractor. It worked, but there were a lot of little things to fix up and considering I had never

drained or replaced all the oils and filters, I figured I should do it.

When I was done, the '303' combination Gear / Transmission / Hydraulic oil leaked out the bottom like a sieve.

I figured I had overdone the cleaning with a pressure washer and caused it.

Two weeks ago we got a notice in the mail about a big class action lawsuit over the brand of "Tractor Fluid" I used.

They are claiming it was a bad formulation and among other things eats up the seals.

 

The carb is a Series 228 downdraft Zenith with an adjustable main jet.

The position of the Idle screw makes it a 228 rather than a 28. They both use the same rebuild kit.

Getting that all adjusted is the next thing on my list.

 

One of the engine manuals mentions a Wick in the center of the distributor shaft under the rotor.

Can/Should I pack some cotton balls or felt in there and saturate it with 30 wt. oil?

 

Yes, that picture is the loader in question.

Mine does not have the optional door or glass.

Due to how they were manufactured and used there always seems to be a lot of modifications guys have made over the years.

 

It's not clear in that picture, but the front wheels contain a 3:1 planetary gear reduction built into them.

That horizontal bar locks onto a splined shaft connected to the sun gear and is designed to be removed.

That disconnects them from the drivetrain. The single rear wheel has a mount point for a tow-bar.

The idea was to tow them with your dump truck to the gravel pit or temporary batch plant site and use it short term then easily take it home.

 

The Industrial engine manual I have does not seem to cover the front pulleys shown above with the timing mark.

The inner one with the timing mark drives the water pump and generator.

The outer 3 drive a very large hydraulic pump that powers all the hydraulics.

 

Is it possible the inner one contains a dampener or balancer of some sort and the load when running twists them and the timing mark out of

position when it's running???

 

My explosion I mentioned earlier blew out and ruined the gaskets for the side valve covers.

I am cutting some new ones out now, it's not sitting level and leaks a lot of oil.

 

Once I get them on I'm going to disconnect the Hydraulic pump and generator belts to see if I can feel any play and if the timing marks end up

closer to where they should be.

 

Thanks for all the suggestions.

Marc

 

 

[maok]

Quote

The Hot Spark docs say "The timing may need to be adjusted by as much as 30 Degrees" after the conversion.

 

The reason for this is that the electronic pickup (lobe sensing or hall effect magnets) maybe in a different position in the distributor to where the points were, hence the radical adjustment that maybe required. It doesn't mean you are actually advance by 30deg when adjusted and correctly timed.

[Marc123]

That is what I presumed.

Disconnecting the hydraulic pump didn't change anything.

The whole assembly appears to be solid. 

The parts manual lists it as a PTO pulley.

Inside it there is what a presume to be a threaded nut with a hole in the center and two angled teeth. I presumed it was for an external crank starter and the angled teeth would kick it out once the Engine starts. Maybe it's to drive something else. 

[billrigsby]

31 minutes ago, Marc123 said:

Inside it there is what a presume to be a threaded nut with a hole in the center and two angled teeth. I presumed it was for an external crank starter and the angled teeth would kick it out once the Engine starts.

 

 

Assuming this is on the end of the crankshaft,

Yes, that is exactly what it is, does not drive anything else.

 

 

Edited October 30, 2021 by billrigsby