Yanmar Hammer quieted by Power Service

California · Feb 19, 2004

I've been tinkering to get a neglected but fundamentally solid 20 year old Yanmar back into top condition. When I bought it the seller demonstrated 'easy starting' which included slow cranking then lots of poorly burned exhaust smoke in the first 10 seconds. At least it had a new starter and the compression seemed tight and even.

Also the infamous "Yanmar Hammer" (fuel knock, especially loud on 2 cylinder Yanmars) seemed overwhelmingly loud below 1800 rpm cold and persisted down to 1300 rpm warm. The seller said it always sounded like that in the year he owned it. Everything I've read says "they all sound like that".

I replaced the battery which fixed the slow cranking, but the sooty startup and the fuel knock still seemed to deserve attention. I read everything I could find here on fuel quality and fuel knock. It ocurred to me the tank likely held summer diesel several years old, since I was told the tractor was infrequently used as a loader in the past several years.

So I experimented putting 50% lamp kerosene in the fuel filter bowl. This lamp kerosene is also old, part of Dad's stuff I am gradually clearing out of the barns. It looked clean but I filtered it through coffee filters anyway. This seemed to start easier and smoked a lot less but still had the same overwhelming fuel knock sound.

I made up a second test batch of 60% lamp kerosene, 40% red diesel from the tractor's tank, and Power Service (white bottle) at the label recommended maximum strength of 1:200. (A blunt plastic hypodermic from an inkjet refill kit was just right for measuring 5cc per quart/liter of test fuel).

Wow - what an improvement! The tractor started instantly like a new Mercedes and idled cleanly. No soot. Fuel knock was nearly gone and it would idle down to almost 800 rpm cold without much clatter.

Thanks to Bird and others who have posted recommending Power Service! I've always thought fuel and lube additives were snake oil but in this case the cetane improvement (and maybe some other magic in Power Service) were exactly what I needed to make this fuel usable.

I have a few gallons of kerosene and several quarts of first-generation 2 cycle oil in the barn that I was going to take to the county hazardous waste collection. Any advice on blending this stuff with Power Service to use as diesel fuel? I have already installed a fresh fuel filter element and also a pre-filter (a cheap auto gas line filter in front of the real fuel filter) so I don't think particulates are a big risk. Reading about biodiesel, it seems that anything that will go through a filter is usable for diesel fuel if it has sufficient lubricity and the cetane is improved by additives into the recommended range.

Any comments welcome. Blending unorthodox fuels may start a little discussion!

RalphVa · Feb 20, 2004

Chevron Red Line is good stuff, too. I had to use it in my diesel tank after the car was stored for 4 1/2 years. Used it a couple other times to silence a tiny ping at constant speed.

Ralph

RET · Feb 20, 2004

California,
Maybe you can 'dispose' of that old oil/fuel lying around by adding it in small portions to each tank of fresh diesel with a healthy dose of Power Service or equivalent added to the mix? Should be able to consume it that way over the next couple of months or so.
r

Junkman · Feb 20, 2004

Take that junk to the recycling center.... it is false economy to try to use that in an engine. What will you save in dollars???? $5, $10, $20?????? If you ruin one injector, you will be paying much more than that to do the repairs in parts alone. Don't be cheap, be smart and put that old junk out to pasture.

grainger12002 · Feb 23, 2004

I am with you, Junkman-throw out that old stuff,take it to autozone or someplace but dont mix it with anything,get rid of it !!

MikeInIdaho · Feb 23, 2004

Better yet, give it so someone who has a waste-oil furnace.

California · Feb 23, 2004

Ok, I asked for advice, and thanks for the comments! I won't try to burn that old kerosene and oil for diesel fuel.

I'm just starting out with this 20 year old tractor and after some minor tinkering it starts easily and runs nice. As Junkman was the first to point out it's not worth the risk of damaging that, just to get rid of some old fuel.

I'll start with fresh fuel and add Power Service - based on my experience I'm convinced it improves cold starts.

KiotiJohn · Mar 13, 2004

From the posted pictures:</font><font color="blue" class="small">( Parking the disc for winter. Note it doesn't go uphill very well in soft ground with so much weight hanging off the front of the bucket. This was where it ocurred to me to check for water ballast in the rear tires. There was none. Adding water ballast, 250 lbs per side, was a big improvemen)</font>California, did you add any antifreeze (for anticorrosion) to your water loaded tires? This is important to keep the rims from rusting around the beads. Some use windshield washer fluid as well. John

California · Mar 13, 2004

KiotiJohn,

These are tube-type tires so I didn't think loading them with just water could hurt the rims. Due to the mild climate I don't need freeze protection, and I never thought of corrosion. I'd like to hear if anyone has had this problem when using tubes.

Earlier this week I spent the day mowing and getting a feel for how everything works. I love this tractor. Everything works like it should. It feels well designed and intuitive like a good tool.

Attached photo: After I finished mowing, my wife asked if I could mow her raised vegetable bed. Well, no because of the high border. But at least I gave her a start on the weeding.

(re the original topic: with fresh fuel plus Power Service it purrs now.)

KiotiJohn · Mar 14, 2004

OH, OK, I didn't realize you had tubes. There should be no problem then. I've always admired the Yanmar tractors. I wish they were selling under their name here again, with good parts support like they used to do a long time ago. Hope you're enjoying it (like you wouldn't be!) John