Farm Equipment - CA Rebuild - Engine Ran, but...

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CA Rebuild - Engine Ran, but...

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Category: Allis Chalmers
Forum Name: Farm Equipment
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URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=166392
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Topic: CA Rebuild - Engine Ran, but...

Posted By: Dale (Stonelick)
Subject: CA Rebuild - Engine Ran, but...
Date Posted: 06 Dec 2019 at 1:15pm

Finally, after a timing adjustment, I was able to get my 1951 CA engine to fire using starter fluid. Yesterday, after cleaning the carburetor main jet, I was able to get the engine to run (kinda). I got it to start, running rough, 3 times for about 10 seconds each before the engine would die. I did use starter fluid, but it did run on gas for a few seconds each time. I heard a little knock in the engine. Stopped trying to get it running when I noticed it didn’t have any oil pressue (with a new oil pressure gauge).

Today, after checking the internet for oil pressure/oil pump problems/solutions, I (1) removed the oil gauge and filter and used air pressure to blow out that line, (2) primed the vertical oil filter tube with oil, and (3) replaced the oil filter with a plastic peanut butter jar so I could see if the oil was pumping up the filter tube. I tried to start the engine (used starter fluid): (a) oil pressure was at 5 psi, (b) oil was pumping up the filter tube at low pressure, and (c engine fired but would not start. I put the FRAM C159 oil filter back on: pressure still at 5 psi and the engine fired but would not start.

You all have been very helpful so far, and hoping you can help on the following questions:

Oil Pressure/Pump: (a) is 5 psi sufficient to avoid engine damage, (b) anything else I can do to increase pressure, and (c can I access the oil pump by removingthe oil pan or do I have to break the tractor in half to get at the pump.
Caburetor-Zenith model 61: (a) It has a main jet, but does not have a Fuel Needle (as shown in the parts diagram)- just an end plug. The end plug appears to be stripped (gas leaks out a little) so I ordered a Fuel Needle from Amazon supplier ($17). Is it okay to use a Fuel Needle on this carburetor? (b) I purchased a Zenith model 61 carburetor rebuild kit. It came with a wire clip to attach the needle valve to the float. However, the wire clip was not in the original nor does it show on any carburetor parts diagrams or parts list. Should I use this wire clip or not?
Engine: (a) why would the engine run rough yesterday but not at all today? (b) is my next logical step to fine tune the timing, or something else? Is a timing light the best solution for fine tuning the timing? (c what caused a little knock in the engine? Is it an incorrect gap between the valve push rods and the rocker arms, or something else?

Appreciate any help you can provide.

Replies:

Posted By: Sugarmaker
Date Posted: 06 Dec 2019 at 1:33pm

Dale,

Opinions only here.

1. 5 psi oil pressure is better than none and they dont have much more than 15 at best.

2. carb? that spring clip is like a return spring to keep the needle valve from sticking in the seat. I think they are a good idea and should not affect how it runs.

3. running is good, even rough is better than not at all. Cant answer why but my guess would be fuel or timing. Mist some gas into the open (air cleaner side of the carb).

Timing light will only fine tune the running engine.

The knock? Well that could be a rod bearing? and probably a dozen other things too.

I think your checking all the right things. Take a break come back and check fuel delivery and or static timing again.

When you said rough running was it backfiring or popping?

Regards,

Chris

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D17 1958 (NFE), WD45 1954 (NFE), WD 1952 (NFE), WD 1950 (WFE), Allis F-40 forklift, Allis CA, Allis D14, Ford Jubilee, Many IH Cub Cadets, 32 Ford Dump, 65 Comet.

Posted By: jaybmiller
Date Posted: 06 Dec 2019 at 2:00pm

first, I'd toss away the starter fluid ! It's a 'dry' combustable...kinda bad for engines if used as the sole method of running....

I prefer to the 'suck and spray' method. Use a small 1/8" hose, suck up say a foot of gas, spray into carb venturi, chok, try to start. If timing, compression and spark are reasonably good, engine WILL start..maybe run 5-10 seconds. Time depends on how much gas you sprayed into carb. Too much, it's flooded - too little, runs 1-3 seconds.

Engine needs to run 2-3 minutes to build up oil pressure 5 psi is low, 15 'normal'. Also engine needs to run good 10-15 minutes to warm up in summer for rings to seat,oil to flow everywhere, etc.

I've used a spray bottle, very carfully !, to 'wet mist' into venuri to get engines to run, spritzing just enough to keep rpms up and not stall out.

Open drain on carb, gas should flow out. If it doesn't check float, float valve, tank, etc.

Lightly close the adjustment screws, open up 1 1/2 or 2 turns.Once running, then 'dial in' for smooth operation . Again, engine needs a good 1/2hr run to warm up and be 'happy'.

Jay

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3 D-14s,A-C forklift, B-112
Kubota BX23S lil' TOOT( The Other Orange Tractor)

Never burn your bridges, unless you can walk on water

Posted By: B26240
Date Posted: 06 Dec 2019 at 3:46pm

I'm with Jay about throwing the starting fluid away !! Go thru the ignition timing step by step and make sure you have a bright blue spark to each plug at the correct time. If the carb is the same one that was on it before it should work now but it needs to be clean, also make sure you don't have any vacume leaks. carefully adjust the valve lash. It could be you have not had the engine running long enough for the oil pressure gauge to come all the way up to the pressure the pump will build. In other words in my experiance the motor has to run for a min. or two before the gauge will be all the way up. Keep us posted and throw away the starting flud!!

Posted By: Dick L
Date Posted: 06 Dec 2019 at 6:06pm

The short pipe going into the bell housing is screwed directly into the oil pump.

Posted By: steve(ill)
Date Posted: 06 Dec 2019 at 7:21pm

It runs on starter fluid, but will not continue to run on gas......... that tells you something....... normally the main jet is plugged or passage is plugged.

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Like them all, but love the "B"s.

Posted By: Gerald J.
Date Posted: 06 Dec 2019 at 8:14pm

The shop manual may help:

http://geraldj.networkiowa.com/Trees/Allis-Chalmers-G-B-C-CA-Service.pdf" rel="nofollow - http://geraldj.networkiowa.com/Trees/Allis-Chalmers-G-B-C-CA-Service.pdf

Gerald J.

Posted By: Dick L
Date Posted: 07 Dec 2019 at 7:26am

No better way to check for carburetor problems than starter fluid. If it will run well with a light mist of starter fluid you know valves and timing are very close. That tells you your problem is in the carburetor. Starter fluid is a valuable tool in sorting out problems. Just like selecting the correct size hammer! One will be fine and the other cause damage.