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Carbon Buildup

Old 09-29-14, 09:18 AM
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Carbon Buildup

I have a 1987 n/a that has some issues. I have heard that when a rotary engine has a lot of carbon the car shakes and you lose a lot of power. Both of these things are happening to me and when I say the car shakes I mean the whole car shakes. I have had this problem for about 2 months now and just recently heard of this as a possibility. It would make sense that it has build up because I bought it from a dealer and the guy who sold it to the dealer told them it was a barn car, I was not told this until after I had the car home. If this is a problem let me know and let me know how to fix it and how hard it is to do.
Old 09-29-14, 11:36 AM
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First step, compression test it. If tgat checks out good, put some marvel mystery oil in the chambers and let it sit and rotate by hand. You MAY get lucky and shoot the supposive carbon out the exhaust.....and i do mean MAY
Old 09-29-14, 11:58 AM
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Originally Posted by lduley
First step, compression test it. If tgat checks out good, put some marvel mystery oil in the chambers and let it sit and rotate by hand. You MAY get lucky and shoot the supposive carbon out the exhaust.....and i do mean MAY
I have done a cold compression test and got 90 on both rotors. I will try the oil.
Old 09-29-14, 12:27 PM
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Look up water treatment
Old 09-29-14, 01:58 PM
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welcome to the board.

when does the car shake? idle only? while driving? if so, any particular speed?

has it been tuned up recently?
Old 09-29-14, 02:13 PM
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Originally Posted by dillrx7
Look up water treatment
When advanced searching for "water treatment" type in the name rotaryevolution or Karack in the 'keywords' search box after water treatment. His insight will get you through the process as needed.
Old 09-29-14, 04:56 PM
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Originally Posted by diabolical1
welcome to the board.

when does the car shake? idle only? while driving? if so, any particular speed?

has it been tuned up recently?
the car shakes at 1500 and below. What aspects of tuning it up are there?
Old 09-29-14, 04:59 PM
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Originally Posted by satch
When advanced searching for "water treatment" type in the name rotaryevolution or Karack in the 'keywords' search box after water treatment. His insight will get you through the process as needed.
I have seen about the water treatment and I thought it wasn't advised when there is a lot of buildup because it could get dislodged and do something to the housing or the rotors?
Old 09-29-14, 06:34 PM
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Originally Posted by ChanBagz

I have seen about the water treatment and I thought it wasn't advised when there is a lot of buildup because it could get dislodged and do something to the housing or the rotors?
No matter what if there is carbon buildup your taking that chance
Old 09-29-14, 06:45 PM
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Have you redlined the motor recently? Do you drive it... Like a teenager? Or like a grandma?
Old 09-29-14, 06:46 PM
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Originally Posted by dillrx7
Have you redlined the motor recently? Do you drive it... Like a teenager? Or like a grandma?
I redline it every day and i drive it like a grandma most of the time.
Old 09-29-14, 09:48 PM
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If you read about the process one of the things that can go wrong is the cat becomes clogged. You would normally use a gallon of water per rotor but you don't use the entire gallon at one time but parse it out to two portions so you're dividing up the cleaning process in two different intervals so as to reduce the chance of releasing too much carbon at one time.
Old 09-30-14, 04:22 PM
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Originally Posted by ChanBagz
the car shakes at 1500 and below.
have you searched for vacuum leaks? checked/confirmed timing?

water/steam cleaning won't hurt (at least, it shouldn't if you do it right), but there are other simpler things you should have probably looked at before you came to the conclusion that carbon is causing the symptoms you describe.

What aspects of tuning it up are there?
basically have you checked and/or changed all filters (particularly fuel) and ignition components?
Old 09-30-14, 05:00 PM
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Originally Posted by diabolical1
have you searched for vacuum leaks? checked/confirmed timing?

water/steam cleaning won't hurt (at least, it shouldn't if you do it right), but there are other simpler things you should have probably looked at before you came to the conclusion that carbon is causing the symptoms you describe.



basically have you checked and/or changed all filters (particularly fuel) and ignition components?
I have been having these problems for the past 3 months and I have tried many things and am running out of ideas. I have no vacuum leaks and the timing is good and also have a new fuel filter and have looked at the ignitions coils and they are good, also spark plugs and wires have been replaced as well.
Old 09-30-14, 05:39 PM
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Have you looked/replaced your motor mounts?
Old 09-30-14, 09:06 PM
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Originally Posted by lduley
Have you looked/replaced your motor mounts?
No I have not.
Old 10-01-14, 08:00 AM
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Here's that link for posterity and any future searches....
Rotary Resurrection home of the budget rebuild.
If you don't find another obvious cause for the symptoms and want to try water ingestion I don't think it would harm anything either. It may not help, but it won't hurt. Distilled water for obvious reasons. Not sure if it's addressed in that link, but I'd do a quart or so at a time with a little rest in between, keeping an eye on the exhaust... which will get hot.
Where in Iowa are you btw?
Old 10-01-14, 08:02 AM
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Originally Posted by Sgtblue
Here's that link for posterity and any future searches....
Rotary Resurrection home of the budget rebuild.
If you don't find another obvious cause for the symptoms and want to try water ingestion I don't think it would harm anything either. It may not help, but it won't hurt. Distilled water for obvious reasons. Not sure if it's addressed in that link, but I'd do a quart or so at a time with a little rest in between, keeping an eye on the exhaust... which will get hot.
Where in Iowa are you btw?
I live in Cedar Rapids and thanks for the link.
Old 10-01-14, 08:06 AM
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Ah, I'm at the west end. Going on the "Cruise to the Woods" this week which ends up in Ft. Dodge. Figured I'd ask. Good luck with the car regardless.
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