Im working on a Jacobsen lawn mower with a ford industrial engine. Its a 4 cylinder 1.1 L carburated engine from the late 70s to early 80s. Its from a family of engines called Kent engines. A 1.6 L edition was used in the Fiesta. The only difference is the crank throw. I found parts for it by looking it up under fiesta. I put new rod and main bearings, piston rings, and had head redone. It runs great except for a couple of problems. When you ease into the hydro feed peddle, the rps decrease and when the governor tries to rev it up, it bogs down and stalls. When I try to increase the throttle too suddenly, it stalls. Im getting a timing light tomorrow an hook it up. Any idea what the base timing is? Im guessing the vacuum advance is whacked. Its been sitting for 7 years in a shop in peices because nobody could find parts. Not even jacobsen. It also overheats but I think the thermostat is stuck so tomorrow im gonna knock the guts out of it and put it back in to still slow the flow down enough to absorb the heat. Also, the governor is run off the crank pulley on the front and is mechanical. It looks like it has a place to put oil in it, im wondering if it needs some or even how to fill it properly. If anybody knows these engines, I would appreciate some input.

 

Never actually worked on one, but the 1.6 Kent engine was used in the first Pintos and Capris as well as the English Ford Cortina and was a very popular engine in its day. Of course the automotive version wouldn't have had governer so none of my books would cover that.

I would set base timing at 6º BTDC and see how it likes that, then try advancing it 2º at a time, probably not much beyond 10º-12º at the end.

Is this a crossflow engine (as the later Kent engines were) or is it derived from the early pre-crossflow Kent engine? They actually built an 1100 pre-crossflow engine (intake and exhaust manifolds on the same side of the head) for automotive use in the early '60s...

 

This is a crossflow. The intake and exhaust are not on the same side. I messed with it today got it running half way decent. The thing i cant understand is when i set it 6,8,10 or anywhere near that, it runs like crap and spits through the carb and exhaust when you rev it. I got it set like 20 degrees advanced and it runs pretty good there. When I have the timing set to 10 or where i can actually see the mark while its running, I verifyed that the advance was working when you open the throttle it advances it about 10 degrees or more. It just wont run with that timing. I just had to keep advancing it untill it would take the fuel without spitting. It doesnt spit anymore but it is not exactly right yet. This engine is way oversquare. It has like a 2 inch stroke and 3 inch diameter pistons. Would that have anything to do whit why it has to be so advanced? It broke a belt today so I couldnt test it anymore. Its supposed to have 3 belts on it but the guy says he cant get a matched set so he just runs one, because the other 2 will always come off.

 

Does the mechanical advance work? Have you checked to see if it still advances with the vacuum advance disconnected? How about the cam timing,are you sure it's spot on? Also, have you tried running it with the governer disconnected?

 

I'd make sure that the accelerator pump was working in the carb. Without that, you will get backfires and spitting when the throttle is opened quickly. The vacuum advance could be a little too strong against old springs behind the diaprhagm, leading to backfire and possible stalling when you goose it. You have improved compression, and intake manifold vacuum should be at or near 'new', but the springs have eleventy seven years of being pushed on and could be weak.
Just a thought on the belts, check with Gates Rubber Co. They were a pretty good company in the past, but who knows now.
The Kent was an excellent design, and it is still used in some racing classes. They may be a source of parts, come to think of it.
tom

 

I would double and tripple check the firing order. Two crossed wires could cause this problom. I belive everyone has chased that dragon before.

 

Another thought: Buy a dozen belts, and match up three as best you can. Should be able to get pretty close to 'matched' and have one over tensioned, one right on and one under tensioned. Heck, I don't know what I'm talking about, but that's what I'd do. A single belt is obviously not enough to transfer the power the engine is putting out or they'd not have spec'd a triple setup.
From what I remeber of my brother's Fiesta, the engine had a pulley with a notch out of it and the timing marks were on the timing chain cover. Is it possible that the notched pulley is mounted 90 degrees out on the nose of the crankshaft? Again, it has been 1982 since I last worked on one.
tom

 

I got two gates belts from oreillys and they said even though they were not sold as a matched set that they had the same part number and batch number so they are matched. They have not come off yet. They didnt have three so two is better than one. As for the engine, I gave up on it and another guy, an old guy, is going to tune the carb and timing, because Im not good at that stuff. They never really taught us about carbs and distributors at NADC. Im pretty sure the pulley is on correct because It only has one keyway in the crank. You are correct tom it does have a notch in the pulley that is rather hard to see. I got the base engine perfect, and the other guy is going to put the old school magic on her to tune it up. Thanks for the input guys! My next project is the transmission in a 90 something international dt466 triaxle dump truck. It has a couple of gears missing and no low range, so im gonna tear it out on monday and see if its rebuildable if not we'll get a used one.

 

Also check the power valve in the carb...

And put a stick in #1 splark plug hole to follow piston motion to see if TDC marking is right.

 

Have any pics?

 

I dont know what a power valve is. The pumps working its dribbling gas down the carb when you pump it. I dont know if its supposed to spray or jet or what but this one dribbles. I set the base timing somewhere around 10 btdc and the mower runs good with the choke on, so im guessing its a carb problem. He said he mowed with it like that and it ran like a scalded dog. He said he was cutting grass 2 feet tall in the back 40. Ill be looking for a kit. O'reillys can prolly get one in a week or so. I've moved on to a dump truck and a golf cart now. His yamaha G1 golf cart has a melted piston because of automatic oil injection failure. Thats getting disconnected and using mixed gas. Sorry to get off topic.

 

The accelerator pump on most carbs squirted a small stream of gasoline when the throttle was pushed open quickly. It prevents stumble. The stumble would be caused by the density of the gasoline being higher than the density of air. The air speed right up going into the intake, but the fuel in the passages takes a bit more time to accelerate and get up to speed, causing a 'lean stumble'. The fuel air mix is to lean, and misfires. The pump squirts in a dash of raw fuel, that has not taken the long route through the carb, and is right there right then to keep up with the air motion.. In a rather large nutshell..
tom

it shouldn't drizzle, it should squirt.

 

Hmm, sounds like prostate problems...(sorry, couldn't help it! With a line like that, how could I resist?!)

 

The power valve is a diaphragm valve inside the carb that richens the mixture under low vacuum (high load) conditions.

However, as previously mentioned, if your accelerator pump isn't giving a good solid stream of fuel, that is probably the problem.

 

I remember working on these engines back in the '70s and they were all adjusted lean to make them burn clean. I would try to richen the mixture a little with new jets in the carburetor.

With the governor working remember the spring holds the throttle wide open and the spinning counterweights overcome the spring to slow the engine down. The less the spring pressure the slower the engine will run.