Puppeteer

Author Topic: decarboning....how to?  (Read 1145 times)

Powdermonkey

  • Jr. Member
  • **
  • Posts: 82
    • View Profile
decarboning....how to?
« on: May 17, 2023, 11:35:07 AM »
Hi Folks- I'm just completing the 1,000 hour rebuild on my twin 16/2.  It's been running well, thought I want to KEEP it running well.  Rehoned the cylinders, new rings, and decarboned the head.  Mind you, the carbon buildup on the exhaust side (both heads) was...a good bit.  Not insurmountable, but still a good bit of work.  I suspect the standard mufflers are likewise "coked". 

So, the question:  Other than mechanical abrasion (scraping), is there a better/easier way to decarbon the entire exhaust port AND mufflers?  I'm thinking of trying a pressure washer...anybody got experience here? 

dax021

  • Full Member
  • ***
  • Posts: 228
    • View Profile
Re: decarboning....how to?
« Reply #1 on: May 17, 2023, 08:21:24 PM »
If Glort was still around, I'm sure he'd tell you spray some water down the intake manifold while running, but I've never tried it.  From what I've read though, it works.

Hugh Conway

  • Hero Member
  • *****
  • Posts: 531
    • View Profile
Re: decarboning....how to?
« Reply #2 on: May 17, 2023, 10:30:59 PM »
Hello Powder
I have 3000 + hours on my 6/1 listeroid. Replaced a couple of head gaskets early on before figuring out that the liner protrusion was excessive. Fixed it with a file. Other than that and regular oil changes, no maintenance seems to have been necessary. Still starts an runs as it did way back 12 years ago.
I do decarbonize once in a while by using a spray bottle. A litre of distilled water sprayed into the intake while running at load seems to do it. Do this a couple times a year. I spray until it just starts to reduce RPM.
 Some operators use a water drip feed or siphon to keep things cleaned up. I find that my wife's garden hand spray bottle works just fine.

As always, YMMV
Cheers
Hugh
JKSON6/1  (Utterpower PMG ) Off-grid
Lister 6/1 Start-O-Matic engine......running with PMG
1963 BMW R-27 project

Powdermonkey

  • Jr. Member
  • **
  • Posts: 82
    • View Profile
Re: decarboning....how to?
« Reply #3 on: May 17, 2023, 10:36:25 PM »

Hugh- Do you take off the mufflers when you do this?  Judging by the amount of carbon I "mechanically abraded" from the exhaust side of the head, I'd think it would clog up a pepper-popper muffler....






Hello Powder
I have 3000 + hours on my 6/1 listeroid. Replaced a couple of head gaskets early on before figuring out that the liner protrusion was excessive. Fixed it with a file. Other than that and regular oil changes, no maintenance seems to have been necessary. Still starts an runs as it did way back 12 years ago.
I do decarbonize once in a while by using a spray bottle. A litre of distilled water sprayed into the intake while running at load seems to do it. Do this a couple times a year. I spray until it just starts to reduce RPM.
 Some operators use a water drip feed or siphon to keep things cleaned up. I find that my wife's garden hand spray bottle works just fine.

As always, YMMV
Cheers
Hugh

Hugh Conway

  • Hero Member
  • *****
  • Posts: 531
    • View Profile
Re: decarboning....how to?
« Reply #4 on: May 17, 2023, 10:59:32 PM »
Hello Powder
I do not have a pepper pot muffler installed. The exhaust is a 2" steel pipe that goes into a "Pit-of-Doom" underground chamber. I have removed the pipe at the exhaust port a few times for other reasons, and found no great carbon build-up.
An air compressor filter/silencer is used on the intake. I just unscrew that and spray water directly into the adapter on the cylinder head.
Do a search of the site, you may find info re what others have done. I'm just one guy out in the boonies!
Cheers
Hugh
JKSON6/1  (Utterpower PMG ) Off-grid
Lister 6/1 Start-O-Matic engine......running with PMG
1963 BMW R-27 project

ajaffa1

  • Hero Member
  • *****
  • Posts: 1787
    • View Profile
Re: decarboning....how to?
« Reply #5 on: May 17, 2023, 11:07:46 PM »
Water injection will only clean up the carbon deposits in the cylinder, it won`t do anything for the exhaust ports and muffler. I have never found anything that will clean the exhaust ports other than elbow grease, I doubt that a pressure washer would work but give it a go and let us know. The deposits in the muffler happen because these slow speed engines don`t get the mufflers hot enough to burn off the deposits. If you have a wood burning stove chuck the mufflers in and leave them overnight, the carbon will burn off them, sadly, so will the paint so you will need a can of high temperature spray paint. A blow lamp will do the same thing, I have used this technique many times on mufflers off 2 stroke engines which also have a bad habit of coking up.

Bob

Willw

  • Full Member
  • ***
  • Posts: 143
    • View Profile
Re: decarboning....how to?
« Reply #6 on: June 10, 2023, 11:56:13 AM »
I'm a bit late, but here goes.

I soak my heads and pistons in a full concentrated degreaser called "Simple Green" and within a day or 2 the majority of the carbon is gone, and what is left is very soft and easy to remove.

I see no reason your Pepper Pot could not be submerged in this for a day, hosed out with a garden hose, and repeated as necessary.

This product does not seem to attack aluminum or paint, in my experience, but it does evaporate if left uncovered. I use a 5 gallon bucket with a screw on lid.

I would weigh the muffler before and after starting the process as a means to gauge progress, but bear in mind that any remnant carbon might retain water, so the muffler might get heavier before it gets lighter.

 https://www.homedepot.com/p/Simple-Green-1-Gal-Concentrated-All-Purpose-Cleaner-271010613005/100060853
Daily driver '97 GMC W4 tipper on WVO/Kerosene mix.
6/1 clone standby generator.
Too many projects.

Willw

  • Full Member
  • ***
  • Posts: 143
    • View Profile
Re: decarboning....how to?
« Reply #7 on: June 11, 2023, 02:12:18 PM »
CAUTION: I just removed a few parts from a 3-day soak in Simple Green and there IS some paint removal.

This is the 1st time I have seen this, but it is also the longest that I have soaked anything so please be cautious in using this product.

Also, If the product is dirty ie from previous use, it will leave a film of discoloration on aluminum products which is easily removed with dead-smooth sandpaper.
Daily driver '97 GMC W4 tipper on WVO/Kerosene mix.
6/1 clone standby generator.
Too many projects.

cobbadog

  • Hero Member
  • *****
  • Posts: 1060
    • View Profile
Re: decarboning....how to?
« Reply #8 on: June 14, 2023, 04:50:21 AM »
Using a spray of water when the engine is hot will help a lot. As for exhaust pipes and mufflers remove them and toss in a big fire pitt for a few hours, then rake them out and allow to cool. Most of the carbon would have burnt off and any remaining carbon you will be able to shake out.
Coopernook - the centre of our Universe.