Trying to figure out valve events and TDC

[Mike B]

The engine is a correct era Ford...but not a flathead...but I think the priciple is the same...as I'm trying to figure out if this (Fordson Deisel) has proper valve timing without pulling the injector to check for compression.

Let's start on #1 compression stroke as the #1 valve just closed...just BTDC the mixture is ignited.

At TDC of #1, my assumption would be that the next cylinder in the firing order, it's intake valve should begin to open for it's intake chrge...would this be correct?

Or am I skipping over something?

[rotorwrench]

It would be if the cam is in proper time. You might have better luck with responses on one of the tractor related forums. The Fordson tractor engines don't share much with the cars with the exception of the 9N that was used in some of the early 40s vehicles. The English Ford deisels are a different story.

[Mike B]

That's what I'm trying to determine...if the cam (evidence shows the timing cover has been off before) is in time.

Where I "think" TDC should be (or close) I have to rotate the engine another 20*'s or so to get to my marks...leads me to believe the timing set was not installed correctly at some point.

The tractor guys are pretty good-and have helped me out quite a bit in the past-but questions like I'm asking seem to bit a bit much for the restoration crowd

Thanks...I think you have the same thinking as I do.

[ford3]

on most engines the keyway on the crank is either straight up or down at top dead center

[Walt Dupont--Me.]

Mike, lets do this a little different. If you can see the top of the piston, or stick a screwdriver in the plug hole and feel the piston when it's TDC. I believe this is an overhead valve engine. We'll take the companion cyl. If this is a 4 cyl, 1-4 are companion cyl. SO, with the rocker cover off so you can see the top of the valves on no. 4 cyl, crank the engine right hand rotation and watch the exh valve on no. 4 cyl, when the exh valve is almost closed the intake will start to open, you can rock the engine back and forth and those 2 valve will rock back and forth so both valves will be off the seat, this is called valve overlape, with those 2 valves rocking the piston should be at TDC exh stroke and no. 1 piston will be on TDC compression stroke. If the pistons are not at TDC the valve timing is off. Simple. Walt

[Mike B]

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Thanks Walt...I think is similar to what I mentioned?

i/e #1 at TDC on compression, the intake on the companion (#2 in this case) should begin to open-or soon/close to the event...but be with 4-5 degrees of crank shaft revolution.

Without pulling an injector, I can't verify...concern of pulling the injector on this engine is damage to the injector and I don't have parts locally to replace...but I think we are working on the same train of thought with the valve events.

Why do I take on these problems?

Edit:

This engine has the degree indicators on the flywheel..as as mentioned when I have it set with the intake just opening on #2, then back off to close, I have to rotate a good 20 degrees to find the TDC mark on the flywheel...

I'm just trying my best to convince myself the only way to fix this is to tear a bunch of stuff off

[Walt Dupont--Me.]

What is this, a 2 cyl. engine? Walt

[Mike B]

No Walt, it's a Fordson super major 4 cyl diesel, the firing order is 1 2 4 3 (little unconventional), but is overhead valve..it's in a older Holman Air compressor...as far as I know 4cycle diesels or gas engines, valve events should be the same principle...maybe with different overlaps and such as I don't know if diesels use a scavenging effect or not, but should be within 4-5 degrees (assumption on my part) to a gas engine as both are 4-cycle.

[Mart]

At top dead centre on the non firing stroke the valves should be "rocking," that is the exhaust closing and the inlet opening. Turn the crank and try and judge the mid point as the valves are rocking. If it does not correspond to tdc then the cam timing is out. I had this problem on a y block when I didn't realise the timing was set by a certain number of pins between the marks rather than aligning the marks.

Mart.

[Mike B]

Pretty much what I have seen Mart...unless the flywheel was put in way off, I'm pretty sure someone installed a timing set/etc, and didn't get it correct.

FWIW (and why I think this may have occurred) is in order to get a straight on view of the front of the engine, two radiators (very heavy) need to be pulled, as well as all the sheet metal surround...I see no evidence (worn bolts, chipped paints) that the radiators have even been out, although much paint missing and rolled over timing cover bolts are seen as well as silicon/gasket sealer, sticking out in quite a few places on the timing cover.

Leads me to think someone may have tried to save effort, and pulled things apart with the radiators in place and not being able to accurately line things up, missed a notch on the timing set.

[Walt Dupont--Me.]

Mike, the fireing order is 1243 just like a ModelA ford. BUT, that has nothing to do with the valve timing. no.1 and no,4 pistons are both up at the same time and no.2 and no. 3 are both up at the same time. SO, if you rock the 2 valves on any cyl that piston has to be on TDC exh. stroke, and the companion cyl will be TDC compression stroke. I'm in the habbit of rocking the companion cyl so I know the other cyl is on compression stroke and if I was installing a dist I can have it fireing on no. 1, but the dist or injector timing has nothing to do with the valve timing. You want to know it the piston is on TDC with the 2 valves rocking before you pull the whole front end apart. Other engine like say a Jeep fireing order 1342, still 1-4 and 2-3 are both up at the same time they just fire 1-3 and the Ford fire 1-2ect. So. forget the fireing order and just think about the valve timing. Let us know how you make out. Walt

[Mike B]

I get what you mean now Walt, great explanation and easy for me follow tomorrow.

Thanks for taking additional time with me

[rotorwrench]

The cam is gear driven so it would have to gave been set wrong or major damage occured. You will have to pull an injector if it will gain access to the top of a piston. If not, then that wouldn't help much.

If you are having difficulty running the engine or it won't start, you will also need to have the injectors & injector pump tested. I noticed that a fair amount of parts are still available for the Major series tractors but you may have to get some from the UK. The first motorized vehicle I ever tugged a steering wheel on was a Fordson Major and I was sitting on my Pop's lap. They are damn good tractors. The only reason my Pop sold the old major was to get the full hydraulics of a Ford 5000 and I put a lot of hours on that tractor plus pulling injectors and taking them to the shop to get them tested now and then. The old Fordson we had is still used for mowing the edges of the runway at the local airport of my old home town.

Most older deisel injector rebuilders are familiar with the Simms type pump. It may have lost its oil due to a failed seal then the innards start to rust up & quit pumping. It may need new bearings and a seal. The injector nozzles are still available too.

[Mike B]

Worked like a charm Walt!

Roto, I'm pretty sure the pump is okay, but going to see if I can find a volume spec on it and see about delivery..very possible the injectors need servicing...I'd changed the oil in the pump and made sure the rack was free and the poppets all worked.

Also...no wonder I didn't have any (well...very minimal) slop in the timing

Thanks again all, appreciate the help and I've learned even more today!!

[Manuel]

Hi Mike,
Here are a couple of Fordson sites you can ask for help--

http://www.fordsontractorpages.nl/ph...d158166b85cd69

http://www.yesterdaystractors.com/cgi-bin/boards.cgi

Although you may have been there already.

Manuel in Oz