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Rotary Engine Building, Porting & Swaps All you could ever want to know about rebuilding and porting your rotary engine! Discussions also on Water, Alcohol, Etc. Injection

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Old 06-20-2004, 09:28 PM   #1
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Well, my new project car came with a street ported 13BT that I have confirmed with the builder that was done less than a year ago. I was told by the previous owner that it never ran right, and after tearing into the car I can pretty much tell why it never ran right, to be honest with you, I don't see how the motor ever ran in the first place.



Since it ran like complete crap for year, the chambers have to have some of worse carbon build up I have ever seen on a engine, I have seen 12As with 150k-200k miles look cleaner than this motor.



Well I guess the question of the hour is, is their a good way to clean out the carbon build up in the motor with out pulling the motor apart? This little project has went well over 8k over budget already and as much as I would like to go through the motor, I have to know when stop, so I would rather not go into the motor if I don't have to.



If I do, well its better to do it now with the motor on a engine stand.
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Old 06-20-2004, 10:09 PM   #2
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best way to do it is to drive the ****** hard! carbon burns off you see
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Old 06-20-2004, 10:11 PM   #3
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j9 and carbon dont get along

how do u know if it has carbon buildup realyl bad did u look thru exahust ports?

or di du take motor appart? and by chambers u mean rotors?
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Old 06-20-2004, 10:58 PM   #4
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Quote:
Originally Posted by kahren' date='Jun 20 2004, 07:11 PM
j9 and carbon dont get along

how do u know if it has carbon buildup realyl bad did u look thru exahust ports?

or di du take motor appart? and by chambers u mean rotors?
i have no problems with carbon, it doesnt stick around long enough Click the image to open in full size.
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Old 06-20-2004, 11:11 PM   #5
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Engine is stripped down to a "short block" You can see through the exhaust ports and its pretty bad, I wouldn't doubt the motor didn't have a stuck seal or two. I could tear it down, but I would rather not.
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Old 06-20-2004, 11:57 PM   #6
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didu ever check compression, sometimes peopel are too quick to blame the motor when its really everythign else thats broken
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Old 06-21-2004, 01:24 AM   #7
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i have recently bought a used engine and from my inspection it had decent carbon build up in it. my original plan was to not tear it down so i soaked the internals with MMO and cranked it over a ton manually to try to clean some of the **** out. once i finally decided to tear it down to port and rebuild, the majority of the carbon came off with some warm water. i say try to really soak it and let it sit to eat up some carbon and then drive the **** out of it.
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Old 06-21-2004, 08:37 AM   #8
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The whole point was to try to get some of the carbon out while its still on the engine stand. I would like to get it back in the car in a next few weeks... at least that is the plan.
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Old 04-02-2010, 07:16 PM   #9
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Quote:
Originally Posted by T72FC View Post
Well, my new project car came with a street ported 13BT that I have confirmed with the builder that was done less than a year ago. I was told by the previous owner that it never ran right, and after tearing into the car I can pretty much tell why it never ran right, to be honest with you, I don't see how the motor ever ran in the first place.



Since it ran like complete crap for year, the chambers have to have some of worse carbon build up I have ever seen on a engine, I have seen 12As with 150k-200k miles look cleaner than this motor.



Well I guess the question of the hour is, is their a good way to clean out the carbon build up in the motor with out pulling the motor apart? This little project has went well over 8k over budget already and as much as I would like to go through the motor, I have to know when stop, so I would rather not go into the motor if I don't have to.



If I do, well its better to do it now with the motor on a engine stand.




Try using methanol or any kinda of carbon build up cleaner. Run it throuh yor vacum system it cleans it up pretty well. make sure you replace your spark plugs afterward
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Old 04-03-2010, 04:17 PM   #10
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Quote:
Originally Posted by T72FC View Post
Well, my new project car came with a street ported 13BT that I have confirmed with the builder that was done less than a year ago. I was told by the previous owner that it never ran right, and after tearing into the car I can pretty much tell why it never ran right, to be honest with you, I don't see how the motor ever ran in the first place.



Since it ran like complete crap for year, the chambers have to have some of worse carbon build up I have ever seen on a engine, I have seen 12As with 150k-200k miles look cleaner than this motor.



Well I guess the question of the hour is, is their a good way to clean out the carbon build up in the motor with out pulling the motor apart? This little project has went well over 8k over budget already and as much as I would like to go through the motor, I have to know when stop, so I would rather not go into the motor if I don't have to.



If I do, well its better to do it now with the motor on a engine stand.




Its too late now, but, before a rebuild, if the engine still runs:



Get it hot. At fast idle, slowly pour in a pint of water into each housing. Pour just fast enough that the engine does not stumble.



Not for use if the car still has a converter installed. The carbon will ruin the converter.



There will be no carbon in the engine on tear down.



If you pour too fast you may shatter the porceline on the plug and hose the housing.



Have you never seen a piston engine that has sucked in a head gasket? Piston crown and cylinder head clean to the bare metal. As though it had never been run. Been doing that for 40 years now.



Make an awfull mess behind the car aft of the exhaust pipe. Exhaust may smoke for a while.



Works great on piston engines as well.



For engines out of the car, use Easy Off oven cleaner sprayed into each chamber face. Let it sit for a few hours. Hose it out with water. Dry chambers with compressed air. Spray in WD-40.



The stuff burns skin.



Cover up. Wear eye protection.



Change the oil.



Lynn E. Hanover
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Old 04-03-2010, 04:17 PM
 
 
 
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