Losing Power

[300zx]

I am losing power at full throttle on my new to me B2150 with 682 hours showing. I have had the tractor for about 2 months now and have only used it occasionally around the house for lifting and moving things without any problems. This morning I traveled about 1/2 mile on the road to pickup my 5 ft finish mower. The road was hilly and I noticed that it was losing rpms pulling up the hills. I picked up the mower and started mowing some fairly tall grass. At first it ran perfect. After a while it lost rpm/power under load and began to miss. Under less load, the miss would go away. By the time I finished about 1/2 hour of mowing and got it home, it was worse under load, but ran fine at idle. The previous owner had changed the fuel filter and said he had put on a new fuel pump. I am guessing this has been a problem before. I am fairly new to diesels. If an injector goes bad, does it miss at all rpms or just under load? Can it be valve clearance? As the engine heats up under load, what little clearance it has is lost and I am losing compression? Any help would be appreciated.

John in VA

 

[Bulldog]

The first thing that comes to mind is either dirty fuel filter or maybe water in fuel which again will be dirty fuel filter. Might try some conditioner and a new fuel filter just to be sure for yourself. Eliminate the easy things first.

 

[Eric McCarthy]

Agreed.....

 

[300zx]

I got the filter and will put it in tomorrow. The fuel has conditioner in it, but I will double it up. If the fuel has water in it, can it be seen in the clear fuel filter housing? I have a valve cover gasket coming in on Saturday morning. It is leaking, so I might as well adjust the valves and replace it while I am in there.

John in VA

 

[hodge]

You might want to check your tank for obstructions at the pickup. Something could be in there moving around, and as you use the tractor, the flow of fuel pulls it to the pickup. That may not be it, but you should at least eliminate it. Insufficient fuel pressure to the injection pump can cause reduced power.

 

[Apogee]

If there is a petcock on either the top of the fuel filter housing or on the outlet of the fuel tank, make sure it's turned fully on.

On one of my tractors, it had been bumped part of the way closed and it acted exactly as you describe.

 

[Stumpy]

Yeah try the valves and the filter first.

Does it run rough or ping at all or just work hard and stall? The extra black smoke is indicitive of incomplete combustion. This could be caused by poor atomization from dirty inectors, low injection pressure, lack of air or compression or it could be normal for your injector settings under high load.

I like your valve cleatance theory, see if they'te tight before you adjust them.

 

[300zx]

Stumpy, I understand what you are saying. It doesn't run rough or miss at low to mid rpm and runs well in the first 15 minutes. Once hot and loaded, the rpm's go down and it begins to miss. There is no black smoke while it is missing which makes me think it is not the injector. That may also rule out the valve clearance, but I am going to check them anyway. It sure seems like it has to be a lack of fuel. I plan to change only one thing at a time to see what is causing it. Tomorrow will be the fuel filter and checking for trash in the bottom of the tank.

John in VA

 

[Stumpy]

Opps, could've sworn you said something about black smoke. I must've crossed a wire somewhere between the ears.

In that case it does sound a bit like fuel starvation though I'd expect it to cough out all together and then restart, rather than just bog down but Apogee's testimony says otherwise. Let us know what you find.

 

[300zx]

See what you think, but the fuel filter looks like the culprit for fuel starvation!! LOL! So much for the PO telling you the tractor has just been serviced. If the filter looks this bad after 2 months of only 3 hours of work, I had better take the tank off. I'm just kidding. I don't believe the filter has been serviced in a long time. I do plan to remove the tank and clean it as well as the hoses to the filter. The last picture shows the contaminants in the fuel that dripped on drip pan after I removed the filter. Thank God for filters and hopefully an easy fix. Now I will have to check all of the tractor service areas!

Sorry I bothered everyone with such a simple issue, but maybe other will learn from it. I will let you know how it goes.

John in VA

 

[Bulldog]

Maybe a new filter will have you going again. My new question is how much trouble did you get in for using the wifes measuring cup for diesel fuel. My wife walked by as I was looking at the pics and I was threatened just for thinking about it. lol

 

[hodge]

See what you think, but the fuel filter looks like the culprit for fuel starvation!! LOL! So much for the PO telling you the tractor has just been serviced. If the filter looks this bad after 2 months of only 3 hours of work, I had better take the tank off. I'm just kidding. I don't believe the filter has been serviced in a long time. I do plan to remove the tank and clean it as well as the hoses to the filter. The last picture shows the contaminants in the fuel that dripped on drip pan after I removed the filter. Thank God for filters and hopefully an easy fix. Now I will have to check all of the tractor service areas!

Sorry I bothered everyone with such a simple issue, but maybe other will learn from it. I will let you know how it goes.

John in VA

Don't be sorry! Someone will learn from it, and a photo is worth a million bucks! Keep passing on the experience and knowledge! And the fact that you should seldom take the word of the previous owner when it comes to maintenance. The only way to know for sure is to do it yourself.

 

[300zx]

My new question is how much trouble did you get in for using the wifes measuring cup for diesel fuel. My wife walked by as I was looking at the pics and I was threatened just for thinking about it. lol

I get the "hand me downs". You can't see it, but the measuring cup has a broken spout and not used in the kitchen anymore, so I use it to measure chemicals. I also have the "hand me down" washer and dryer for my dirty towels and cookie sheets that are great for tearing down carbs.

I took the fuel tank off this afternoon. The bottom had lots of slimy junk in it. I took out the fuel sender and used a 4000 psi hot water pressure washer to clean it out. It took several cleanings to get it where I was satisfied. The gasket on the top of the differential casting is leaking, so while I have the seat and tank out, I need to pull it and seal it. So I won't know until tomorrow how she runs with a clean filter and plenty of fuel.

John in VA

 

[300zx]

Don't be sorry! Someone will learn from it, and a photo is worth a million bucks! Keep passing on the experience and knowledge! And the fact that you should seldom take the word of the previous owner when it comes to maintenance. The only way to know for sure is to do it yourself.

Hodge, you are right about the word of PO's. I have a friend who bought a small air cooled engine that was supposedly overhauled. When he got it home and installed, it hardly had any compression. When he asked the PO what he meant by recently overhauled, the man told him he had recently put points and plug in the engine!!

John in VA

 

[ipz2222]

Afriend of mine bought a boat once, the owner told him all this stuff that had been done to it. We later found out , all the stuff that had been done to it was actually , all the stuff that ""needed " to be done to it.

 

[300zx]

It took me longer than expected. The gasket on the lift cylinder/differential cover was leaking oil. So, while I had the tank out, I pulled it to see why it was leaking. The PO had replace the casting because it had cracked. What I found was a crimped and out of place new gasket. That is now repaired, the tank is clean and the new fuel filter is in. When I came back after lunch, I found diesel dripping on the floor. I had put on new hoses, but I checked them anyway. They were not leaking. I now have a pin hole leak in the bottom of the tank. Removing the rust and gunk from the tank has opened it up. On the B2150, the tank is metal and sits behind the seat up against the role bar. I did take the tractor for a short ride and lugged it down on a steep hill. It ran great now that it can get fuel.

Any ideas on sealing a pin hole leak in a metal tank? I think I have a quart can of fuel tank sealer somewhere in the shop. I have never used it. It was on clearance at TSC and I bought it for just such a problem, but I have been wondering if JB weld would hold on a small hole.

John in VA

 

[Stubbyie]

JB Weld claims to seal fuel tank leaks but never tried it. In other similar tanks I've cut off a brass screw of approximate diameter and run it into hole and covered with epoxy. Not fuel but still holds atmospheric pressure hydraulic oil tank. Make certain outside of tank (and screw head) is bare metal and clean (with oilless acetone or ether) to get a good mechanical bond.

There also fuel tank repair kits used by antique vehicle restorers. Pricey but said to work. Creates some kind of permanent internal liner-type coating.

Might consider cleaning WELL with soap and water and try brazing the hole to repair. Silver solder might work well at lower temp than brazing or welding. CAUTION do not get yourself blown up with torch near dirty tank.

You also mention having a shop set of hand-me-down washer and dryer. Same here. Sitting out on pad adjacent to shop, under shed. Washed a load of shop rags one day. Put in dryer and went off to do weedeating wearing earmuffs. Was off away from house and noticed spouse running flat out toward shop carrying fire extinguisher from patio kitchen. Seems my shop dryer had lifted off when the gas fumes lit. Chickens quit laying for a week and shop cat deaf. For sale, slightly used dryer.

 

[Russell King]

Any ideas on sealing a pin hole leak in a metal tank? I think I have a quart can of fuel tank sealer somewhere in the shop. I have never used it. It was on clearance at TSC and I bought it for just such a problem, but I have been wondering if JB weld would hold on a small hole.

This web site has a kit (mentioned in previous post) to fix fuel tanks.

http://www.por15.com/HD-CYCLE-TANK-REPAIR-KIT/productinfo/HDCTRK/

You may be able to get away with epoxy putty if you clean the area inside and outside really well. I have never tried it with a fuel system but used it successfully on other leaky systems.

 

[300zx]

I removed the tank and drained the fuel. I turned the tank over, ground down to metal a dime shaped area around the pin hole, and cleaned it with acetone. I then mixed some JB weld (epoxy) and covered the bare metal area with about 3/32". I let it cure for 24 hours and re-installed the tank. I put about 2 gal of fuel in the tank and so far no leak. The tractor runs great! The stopped up fuel filter was the cause for the fuel starvation. The crapped up tank was the cause for the loaded fuel filter. And the crimped gasket was the cause for the differential cover leak. The tractor is repaired and ready to go back to work! I will be letting it set in my shop for about a week. Hopefully the JB weld will hold and I won't see any more leakage.

John in VA

 

[lourod]

Fill tank with water put cap on turn upside down weld it done this many times on motorcycles.