I have a Blaster that I bought with all kinds of mods, I never received a list but it appears to have everything under the sun. It has a 62T bottom end and WERX racing jugs ontop engraved 985 with a Rive racing head. It has 205lbs of compression on each hole. It dieseled on me in the water my first ride so I bumped the octane from 94 to the Meijer 104 bottle. It started dieseling less. After riding for a while it would start doing it again. So i bumped it to half 94 and half 110 Turbo Blue. It does not diesel on the water anymore but whenever I start it on land it immediately diesels, even when its sat for 2 weeks and is cold. How can I get it to not diesel ? I want to run it on land for 10 sec to blow water out but it immediately diesels and wont stop till I pull the fuel line off the carb. I NEED HELP
Blaster Help with dieseling motor
- Thread starter steff
- Start date
Eli
I'd rather brap than bash
- Location
- Oakley, California
Safest way to kill it in the future is hold the stop button and hold the throttle wide open at the same time. If you have a stock 62T intake manifold make sure it has the spacer plate between it and the cases, a lot of people take these out and don't realize it will cause a major air leak if it is removed.
- Location
- Midland, Ontario, Canada
Do you mean it's running away...if so you have an air leak.
- Location
- Cape May Court House, NJ
Dieseling, or engine run on, is when you shut off the engine and kill the spark but it continues to run. Can be caused by hot spots, high compression, poor fuel quality, etc. I am not familiar with the jug head combo, so I have not suggestions as for a fix, sorry
Thanks for the replies and its not a run away motor, its dieseling, When I pull the spark plugs its keeps running. So the spark plugs are acting as glow plugs ive been told. In the water its fine, which would lead me to believe its not an air leak correct ? The reason im convinced its dieseling is because it was originally only happening when it got real hot. So I kept bumping the octane as it has a lower combustion point and that made a big difference. Now im almost full 110 but not quite(half premium, half 110) and it does not diesel in the water since its being cooled by dual cooling(separate line to head) but only on land when I start it. Newer top end so shouldn't be carbon deposits and it has fresh high grade fuel. Compression is 205 which I am told is a big factor in it dieseling. Still puzzled and want more input!
- Location
- Valley Springs, CA
Clamp all ur fuel lines, make sure ur tank valve is working correctly. Should fix it. My 718 was at 205 and I ran pump gas and it had no effect on dieseling, in fact it was a fuel line that wasn't completely clamped and was leaking.
No all fuel lines are tight they are all tie wrapped, nothing leaking or anything. The thing runs great it just diesels out of water. Im aware compression is only a small partial factor in dieseling issues, which im sure urs is a 6m6 stroke where this is most likely a large stroker motor which plays a different factor in my issue. Would an air leak run fine on water and run away out of water ? I feel like if it was a leak that the leak would cause it to do the same out of water as in the water.
http://www.x-h2o.com/threads/111672-Runaway-motor
Read the linked thread, it should cover everything.
This "dieseling" has nothing to do with compression. It will happen only without a load (out of the water).
Read the linked thread, it should cover everything.
This "dieseling" has nothing to do with compression. It will happen only without a load (out of the water).
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- Location
- Cleveland, OH
air leak somewhere like the others had said. will only "diesel" when there is no load on the engine (out of the water)
Awsome thread there Matt, pretty much covers everything I was thinking. Im going to do a leak down test, if it doesn't leak I will re do all my fuel lines and double check my throttle plate synchronization on the carbs! Best way to do leak down ? Plugs in the intake and exhaust manis and maybe a harbour freight brake bleeder pump/vacuum pump ? Any suggestions ? 8 lbs for 10 min ?
- Location
- Stouffville, Ontario
I use the rubber plugs used to winterize hotub/pool jets. Worked like a charm.
- Location
- United States
Sounds like compression to me. You could always retard your timing and see if that helps. My $0.02
- Location
- Peterborough, Ontario, Canada
Kind of a red neck way to check for intake/bottom end leaks:
Because the problem is from a leak in the engine, ether on the intake parts or in the bottom end of the engine, you will be losing vacuum and letting "fresh" air get into the engine. Im not going to get into the problem with air getting into the engine as you probably already know why thats not good. Possibly dieseling, lack of lubrication, loss of power.....
The quick way to check if you have a vacuum leak is to spray flammable spray onto the parts you want to check for leaks. What this will do is if you have a leak the engine will differ in RPM. Most likely increase, but it could decrease. Whats happening is the flammable liquid is entering through the leak and acting as fuel, thus burning like fuel. If you have no leaks, there should be no change in rpm.
In this particular case you will have to make sure the engine is NOT DIESELING, so keep it on the trailer and have it in water. Then when the RPM's are steady, spray small amounts of spray on parts of the intake. Wait a few seconds, if no change, spray a different part. if you hear change, then you found the leak.
Obviously people are going to disagree with this, because it to dangerous, or sounds crazy. BUT it does work. Iv done it many times on dirt bikes and small engine stuff. I usually find it works on carb parts like intake boots and idle/mixture screws. Little different then a ski, but same principal. A two stoke is simple.
Id maybe have a hose ready or fire extinguisher. but common sense is best dont spray at a spark.
USE brake clean, parts cleaner, or carb cleaner.
Because the problem is from a leak in the engine, ether on the intake parts or in the bottom end of the engine, you will be losing vacuum and letting "fresh" air get into the engine. Im not going to get into the problem with air getting into the engine as you probably already know why thats not good. Possibly dieseling, lack of lubrication, loss of power.....
The quick way to check if you have a vacuum leak is to spray flammable spray onto the parts you want to check for leaks. What this will do is if you have a leak the engine will differ in RPM. Most likely increase, but it could decrease. Whats happening is the flammable liquid is entering through the leak and acting as fuel, thus burning like fuel. If you have no leaks, there should be no change in rpm.
In this particular case you will have to make sure the engine is NOT DIESELING, so keep it on the trailer and have it in water. Then when the RPM's are steady, spray small amounts of spray on parts of the intake. Wait a few seconds, if no change, spray a different part. if you hear change, then you found the leak.
Obviously people are going to disagree with this, because it to dangerous, or sounds crazy. BUT it does work. Iv done it many times on dirt bikes and small engine stuff. I usually find it works on carb parts like intake boots and idle/mixture screws. Little different then a ski, but same principal. A two stoke is simple.
Id maybe have a hose ready or fire extinguisher. but common sense is best dont spray at a spark.
USE brake clean, parts cleaner, or carb cleaner.