trouble diagnosing 83 locked rotory
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trouble diagnosing 83 locked rotory
Well the bug has bitten. Before I even got my 84 on the road, I came across an 83 that is gorgeous and stock. About 87K original miles. Perfect body. Nice white color. The lady who bought it new had just spent several thousand dollars going through the interior and redoing the stock burgandy leather. Rebuilt seats etc... The interior is pristine. Anyhow, I got it for a song due to the engine being locked up. Since it is a very low miler and from a small northern Washington town, I figured that it was a good bet that it was suffering from carbon lock. Seems to foot the bill. Can only be driven certain months and around a small town, with few highway miles, so mostly low RPMs. Older owner so likely not abused too much.
Anyhow, I have tried to turn the engine backwards as suggested in the article about locked motors. I could only get it to go about an inch. Also of note, the plug wires were off the plugs, the plugs were only finger tight and the fan was off, so I am guessing someone may have investigated this.
I should also tell you that the carbon build up on the 4 electrode NGK plugs was thick and nasty. Not really sure how it was firing as dirty as they are.
Is there any sure way to tell if it is indeed carbon locked, or if I have bigger issues short of pulling the thing completely apart? Any tricks? I have put the solvent into the plug holes and plan to leave it in there tonight and see what happens in the morning. Used Marvel Mystery Oil as I already had some lying around. I am just afraid that it may have eaten a seal or something and I may be looking at bigger issues... I don't want to make bad worse by messing with a stuck seal and trying to force it.
Worse case, we will do a rebuild I suppose, or drop a V8 in it. I prefer to keep it rotory just out of principal, but rebuilding one seems pretty expensive.
Thanks
CC
Anyhow, I have tried to turn the engine backwards as suggested in the article about locked motors. I could only get it to go about an inch. Also of note, the plug wires were off the plugs, the plugs were only finger tight and the fan was off, so I am guessing someone may have investigated this.
I should also tell you that the carbon build up on the 4 electrode NGK plugs was thick and nasty. Not really sure how it was firing as dirty as they are.
Is there any sure way to tell if it is indeed carbon locked, or if I have bigger issues short of pulling the thing completely apart? Any tricks? I have put the solvent into the plug holes and plan to leave it in there tonight and see what happens in the morning. Used Marvel Mystery Oil as I already had some lying around. I am just afraid that it may have eaten a seal or something and I may be looking at bigger issues... I don't want to make bad worse by messing with a stuck seal and trying to force it.
Worse case, we will do a rebuild I suppose, or drop a V8 in it. I prefer to keep it rotory just out of principal, but rebuilding one seems pretty expensive.
Thanks
CC
#2
Engine, Not Motor
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MMO is just "wax mud" (see the MSDS) and will do little against hard carbon. Use carburetor cleaner. The best bet would be to pull both the intake and exhaust manifolds so you can get at the inside of the engine directly. By using the spark plug, intake and exhaust ports, you can soak all sides of the rotor and perhaps even inspect a few apex seals.
There is the possibility that an apex seal has rolled out of a groove and jammed up the engine.
There is the possibility that an apex seal has rolled out of a groove and jammed up the engine.
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Got her loose. I went back and forth this morning as it had time to sit all night. It would still hit a rough spot so I worked it back and forth. Pretty soon it was spinning freely and rotating easily. The plugs look AWFUL. totally caked with hard carbon. I tried to start it and had no success. Didn't sound like it was trying very hard, but it is spinning easily with the starter now. And it seems to be even as in it doesn't go faster and slower. Hopefully this denotes that it was just a carbon problem. Any thoughts?
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There is a new component to this, I realized as the sun was going down that the last guy had been fooling with the distributor and its loose. Not sure what the timing should be. Havent gotten a shop manual yet. Any tips?
thx again. CC
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Setting the timing is easy. Rotate the engine until the pointer lines up with the yellow mark on the pulley. Pull the dizzy and rotate it so that the dimple on the gear matches the pointer on the dizzy body. Now reinsert while holding the rotor steady. Make sure to get the wires connected properly (yeah, we've all been there).
I would still highly suggest pulling the manifolds and attacking the carbon directly with carb cleaner. Now that the engine rotates, this will also allow you to inspect the apex seals via the exhaust ports.
I would still highly suggest pulling the manifolds and attacking the carbon directly with carb cleaner. Now that the engine rotates, this will also allow you to inspect the apex seals via the exhaust ports.
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Setting the timing is easy. Rotate the engine until the pointer lines up with the yellow mark on the pulley. Pull the dizzy and rotate it so that the dimple on the gear matches the pointer on the dizzy body. Now reinsert while holding the rotor steady. Make sure to get the wires connected properly (yeah, we've all been there).
I would still highly suggest pulling the manifolds and attacking the carbon directly with carb cleaner. Now that the engine rotates, this will also allow you to inspect the apex seals via the exhaust ports.
I would still highly suggest pulling the manifolds and attacking the carbon directly with carb cleaner. Now that the engine rotates, this will also allow you to inspect the apex seals via the exhaust ports.
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#8
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Give each of the apex seals a visual inspection as you rotate the engine. Puch on each one with the end of an unsharpened pencil, they are "spring loaded" and should move freely against the springs.
Grab a couple cans of Seafoam and work it through the motor, let it sit for a weekend. You can also dump a couple of ounces down the carb when it comes time to attempt a start, which will help deal with the flooding issues you will no doubt experience.
Good luck.
.
Grab a couple cans of Seafoam and work it through the motor, let it sit for a weekend. You can also dump a couple of ounces down the carb when it comes time to attempt a start, which will help deal with the flooding issues you will no doubt experience.
Good luck.
.
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do it Right the first time,and you will be rewarded.
make sure that you follow the advice of Kentetsu about the Seafoam.It works good,and will take Crap out of the internals..enough anyways to loosen up the apex seals so that they will be "springy enough" to make a proper seal and give you decent compression.
Check teh compression before you spend Money on the Stuff below.It could save you in the long run.
Clean out the Fuel system,Oil and filter,new plugs,wires etc.Good Coolant,new thermostat.
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Checking the compression at this point is a little, um, pointless. We can be pretty sure that he has carbon issues, which can prevent good sealing of the apex seals. And we can also be quite certain that the motor is currently flooded, which will return a terrible compression reading.
My advice as above, then just get her started. Once started, you can run her a bit to get everything worked loose, blow some of the carbon out, etc. Once you get her running, she should improve on her own as you work your way slowly up to redlining it and let it clean itself out on it's own.
My advice as above, then just get her started. Once started, you can run her a bit to get everything worked loose, blow some of the carbon out, etc. Once you get her running, she should improve on her own as you work your way slowly up to redlining it and let it clean itself out on it's own.
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Put in a new set of plugs and reset the timing the best I could without a light. Dont have one anymore as I haven't owned a car with a distributor for years. She fired right up! A bunch of oily looking fluid and white smoke was pouring out of her for quite a while. She runs smoothly but with VERY little power. zero to sixty in about 10 minutes. Idles great til I put it in gear, then idle drops a bit and runs really choppy. I plan to run some seafoam through her tomorrow. I figure I will have to work the junk out for a bit. Seems to run better the more I run her. No overheating issues, and smooth idle until I put it in gear. I am hoping it is just the carbon hurting things. Time will tell.
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Well, I decided to go driving, try and loosen her up a bit. It seemes to run worse the warmer it gets. When I first started out it idled smoothly but around 2K rpm, and it would still run when I put it in gear. Its an auto. After driving for a half hour or so, gently, it wouldn't idle anymore no matter what I did and occationaly died even driving down the street. If I tapped the throttle, it would stay running, but if I kept constant pressure on the throttle of any nature, it just died. The idle became very irratic. I am thinking I must have a vaccum leak somewhere, or perhaps between the carburetor and the manifold. At least in the piston engines I have dealt with that would explain both the irratic behavior of the idle, and the lack of power. I think I will try to diagnose that tomorrow.
Any thoughts?? I could really use some guidance here. Thx. CC
Any thoughts?? I could really use some guidance here. Thx. CC
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