Bobcat 632 - Converting to solid state ignition

[RandyL]

I'm happy that you worked your way through it, and that it started. What did you use for ignition? The last I recall you were working to get the spark plug wires on correctly.

 

[brdgbldr]

Are these valves inside the distributor? Thanks!

Piston valves. They are under the valve cover on top of the engine. When they are loose they make a loud tapping sound. You should look for videos online before tackling this yourself.

 

[bobcatzack]

Sounds good - will review some videos as a start, thanks!

 

[bobcatzack]

I'm happy that you worked your way through it, and that it started. What did you use for ignition? The last I recall you were working to get the spark plug wires on correctly.

Hi Randy - thanks!
Yes it was an ordeal, first I tried fitting a Pertronix electronic ignition conversion kit. The item was shipped did not fit the brown cap distributor, but I forced it on anyways (by drilling a bigger hole in the magnet fitting etc). Played a lot with switching plug wires around (experimenting with the 1-2-4-3 firing order. At one point the Bobcat did start but was running rough. So I ended up getting a completely new distributor (from Walmart online because I think it is much easier to do a return if it did not work out). See pic attached. This new distributor actually fitted well, and fingers crossed, I got back to tinkering with the plug wires, slightly rotated the distributor clockwise / anti clockwise - until all of a sudden like magic, the Bobcat fired up!
So now I am still trying to learn how to time the engine (bought a simple timing light etc). The reason is, it takes quite a few cranks to get the thing going when I attempt to start it first time during the day. Once warmed up, it starts fine (I am suspecting this really has to do with the fuel system, dirty carburetor perhaps?). In any case, it does feel good that it starts and runs. I am starting to use it a bit around my horse barn for now.

 

[Tango-Charlie]

I have a 742B that I converted to the Pertronix too. One thing I found was I had to replace the original spark plug/coil wires because they were solid core and with the electronic ignition, if I recall correctly, they had to be the newer non-solid wire center wires. I bought new wires, installed them and it fired right up and still running great. Just food for thought.

 

[adalmi]

On the 742b I added the pertronix distributor instead of the points, left the same coil and wiring and it works well.
Did you upgrade your coil and that is why you had to change the plugs and wires? I actually bought the coil suggested by the pertronix system and was wondering if I should install it. I guess I don't want to fix that is not broken.

 

[Tango-Charlie]

Yes, after adding the Pertronix electronic module to my existing distributor I also upgraded the coil to the Pertronix Flame Thrower II coil that was recommended for the electronic distributor module. I fired it up with the original plug wires and it was missing bad. I checked the plug wires and found that they were copper core. I then either read the fine print in the instructions, FAQ's, or lots of online forums and it was always recommended to replace the original copper core spark plug wires because "Copper is never recommended for Electronic Ignition" and "Pertronix recommends the use suppressor core plug leads". I replaced them with the recommended wires and fired it up with no missing and has been a solid runner for several years. I'm so glad I did away with the points and went to the Pertronix electronic ignition. I even changed out the points in my IH 656 tractor to Pertronix and glad I did.

 

[Jerry01314]

Hello, When I did my 742 with the kit.I connected a timing light because the gap it said and the way the light worked were not equal. When I got the light to look smooth I tightened it up and ran it since.
Probably 20 years. The gap was twice as big as it said or something like that.

 

[bobcatzack]

HELP!! A new thread I tried to create has been awaiting forum approval for 48 hours now! Here's what I was hoping to get help on:


As mentioned in prior posts, I have a 1978 Bobcat 632 with Ford KSG416 4-Cylinder that I bought a couple of months ago. It starts and runs now but is consuming coolant by the gallons .. with white cloud-like fumes coming off from the exhaust pipe .. then within about 5 minutes running at idle, the coolant level drops (since it evaporates so quickly) and the engine starts heating up!
Being a rookie, I am not sure what is going on but from reading various websites and forums I gather that the head gasket might be blown .. and as such the coolant leaks into the combustion chamber to burn off and evaporate (fast!).

I have no idea how I would be able to do this alone, but contemplating pulling the engine and see if I can get to the head gasket .. and possibly replace it. From experienced folks in this forum, can I get some suggestions for the following:

(1) can the engine be pulled without the hoist that everyone seem to use? I don't have such a hoist and am thinking of creating a wooden platform behind the Bobcat to possibly slide the engine out .. is that even practical?

(2) If I indeed was able to pull the engine out, should I look into actually rebuilding it (if pistons don't look right etc.)? If so, is that a very difficult and challenging task? Very expensive and time-consuming?

(3) Any other related advise from experts would be highly appreciated!

MANY THANKS!

Quick Background:
(A) Replaced radiator / radiator hoses (B) Added new electronic ignition distributor / flame thrower (C) New spark plugs (D) New starter (E) New carburetor (F) Compression tests at 110-90-110-110 (G) Engine is always oily from outside with tons of sludge at the bottom (H) Hydraulics seem to be fine - bucket is able to lift and maneuver 900 pound round bales for my horses (I) I realize that I made a bad decision buying this Bobcat, but at this point I feel if I put enough effort (and money!) to get it running correctly, it might be a useful addition to my homestead (I) So far I have about 6K into it.

 

[spitzair]

Zack,
Not sure if I'd call buying that machine a bad decision, we've got a few bugs to sort out and once that's done you should have a very good little machine there. I think you're right with the head gasket being shot, that probably also explains why the 2nd cylinder compression is lower than the rest. You can easily just slide the engine out onto a stand behind the machine, you just unbolt the subframe, it's held in with 4 bolts and the whole affair just slides out. You'll just have to lift it an inch to clear the lip at the rear of the engine compartment. Then you have all the room you'll need to work on it. Once you have the head off you'll be able to tell pretty quick if it is indeed the head gasket, hopefully it's not a cracked head…

 

[bobcatzack]

Thank you for the encouragement, much appreciated! Based on your advise, I will plan to proceed and pull the engine and go from there (hopefully won't find a cracked head!!). I will start by building a stand that would be just the right height to slide the engine onto - perhaps even add wheels to it so I can move the stand around easily (it will have to be quite heavy duty to carry the heavy engine!).
Regards,
Zack

FYI
I will attach a video I took tonight on how the engine runs at idle - I have the radiator cap off - if I put the cap on and tighten it, immediately dense white smoke comes out the exhaust pipe and soon engine starts heating up. Strange that the engine does not heat up and no fumes are produced if the cap is off! Perhaps less pressure inside to push the coolant into the combustion chamber? Also noticeable in the video is exhaust fumes coming out of the engine oil cap opening - is this oil blowby or exhaust I cannot tell.

 

[Ster1]

You don't need a hoist to pull the engine, but a forklift does come in handy. In any case, the engine and engine bracket come out as one unit. 4 bolts on the bottom of the machine, disconnect fuel, coolant (you gotta drain it) hoses, throttle linkage, exhaust system, disconnect harness plug, remove battery, and just pull straight back. You might need to pry it up a little, but it comes out. Maybe a stack of pallets would help hold it up.

 

[Ster1]

By the way, there's a YouTube video out there showing a guy who had to reach in toward the fan from the front of the machine to allow the coupler to disconnect. You don't need to do that. It's a splined shaft and there's no set screw or anything. It just pulls out.

 

[bobcatzack]

You don't need a hoist to pull the engine, but a forklift does come in handy. In any case, the engine and engine bracket come out as one unit. 4 bolts on the bottom of the machine, disconnect fuel, coolant (you gotta drain it) hoses, throttle linkage, exhaust system, disconnect harness plug, remove battery, and just pull straight back. You might need to pry it up a little, but it comes out. Maybe a stack of pallets would help hold it up.

Great! Thanks for laying out the engine pull steps! I might try good quality rollers under the pallets as I would somehow need to drag it indoors where there is warmth .. the garage in the Chicago winters gets pretty cold

 

[bobcatzack]

By the way, there's a YouTube video out there showing a guy who had to reach in toward the fan from the front of the machine to allow the coupler to disconnect. You don't need to do that. It's a splined shaft and there's no set screw or anything. It just pulls out.

Good to know there is no need to reach out from the front. Thanks!

 

[bobcatzack]

video I took tonight on how the engine runs at idle - I have the radiator cap off - if I put the cap on and tighten it, immediately dense white smoke comes out the exhaust pipe and soon engine starts heating up. Strange that the engine does not heat up and no fumes are produced if the cap is off! Perhaps less pressure inside to push the coolant into the combustion chamber? Also noticeable in the video is exhaust fumes coming out of the engine oil cap opening - is this oil blowby or exhaust I cannot tell.

 

[Ster1]

There seems to be a few more issues. That's alot of air bubbling up through the radiator, that suggests blown head gasket or cracked head. Also looks like quite a bit of blowby, that suggests rings have failed. Sounds good though. You can still get gaskets and rings and such for that 1.6.

 

[Ster1]

Great! Thanks for laying out the engine pull steps! I might try good quality rollers under the pallets as I would somehow need to drag it indoors where there is warmth .. the garage in the Chicago winters gets pretty cold

What part of Chicago? I'm from the burbs (La Grange Park). I'm actually going back there to see some family around new years.

 

[bobcatzack]

You will be just about 20 miles from where I live (Bartlett's west side - it's a burb of chicago too). If you would have time, it just might be wonderful to meet up and possibly take a peek at the 632 engine that I would be working at. I will be more than happy to pick you up and drop you back at your place of stay in La Grange. Do let me know if that would be feasible. You may email me separately if needed. Thanks!

 

[Ster1]

Oh sure I know where Bartlett is, you're way NW. I'll be staying in Westmont and Naperville. Sure I'd be happy to meet up. I'll send ya a PM with my number.