Hard snap back portable generator

Daniel 3721

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Is there a standard torque spec for the fly wheel nut?
I'm being ignored by Duro Max customer service. I can't find any torque specs on line or in the owners manuel
 

Daniel 3721

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oh wow. that's got to be a pretty hard stop for the gears to jump time. Unless someone opened it up for some reason prior to you.
I'm not sure what the previous owner did to it. It was clean when I bought it but soon started leaking oil. I treated it like it was brand new, breaking it in according to the owners manual. Also checking the oil before every start. In other words, I don't think it was anything I did or didn't do.
 

shadetree#1

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You will need to replace the ALUMINUM flywheel key. You say the old one WAS OUT OF PLACE. Do you mean it was partly sheared?
You say that after you relocated the out of place key you could at times pull though and start the engine if you pulled it through slowly. This is not a sign that the timing is off internally inside the engine. Usually the timing cannot change internally unless gears break.
What did you see inside that made you think it jumped time inside?

You will also need to carefully adjust the valve lash to minimum specs, especially the intake valve. (most ACR's are on the intake valve and if the valve lash is out of spec or too much clearance the engine will be hard to pull through the compression stroke. Usually the valve lash is set at 1/4 inch past TDC. (or 1/4 inch ATDC (After Top Dead Center of the piston) Most generally the valve lash is .003-.005 cold.

Is that rig electric start?
Reason I ask is I've seen hard to rope pull start engines that would start up ok using electric start.

I really suspect from your description that the unit just needed a new flywheel key and the valve lash adjusted to minimum specs. Valve lash is easily adjusted on a OHV. See youtube for such.

You can find torque specs on-line. (go by the size of the crankshaft nut.
(stud size of the crankshaft)
Most generally 55-60 foot lbs for up to a 25 hp small engine.
Do not use a impact wrench for the tightening torque.
 
Last edited:

Daniel 3721

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You will need to replace the ALUMINUM flywheel key. You say the old one WAS OUT OF PLACE. Do you mean it was partly sheared?
You say that after you relocated the out of place key you could at times pull though and start the engine if you pulled it through slowly. This is not a sign that the timing is off internally inside the engine. Usually the timing cannot change internally unless gears break.
What did you see inside that made you think it jumped time inside?

You will also need to carefully adjust the valve lash to minimum specs, especially the intake valve. (most ACR's are on the intake valve and if the valve lash is out of spec or too much clearance the engine will be hard to pull through the compression stroke. Usually the valve lash is set at 1/4 inch past TDC. (or 1/4 inch ATDC (After Top Dead Center of the piston) Most generally the valve lash is .003-.005 cold.

Is that rig electric start?
Reason I ask is I've seen hard to rope pull start engines that would start up ok using electric start.

I really suspect from your description that the unit just needed a new flywheel key and the valve lash adjusted to minimum specs. Valve lash is easily adjusted on a OHV. See youtube for such.

You can find torque specs on-line. (go by the size of the crankshaft nut.
(stud size of the crankshaft)
Most generally 55-60 foot lbs for up to a 25 hp small engine.
Do not use a impact wrench for the tightening torq

You will need to replace the ALUMINUM flywheel key. You say the old one WAS OUT OF PLACE. Do you mean it was partly sheared?
You say that after you relocated the out of place key you could at times pull though and start the engine if you pulled it through slowly. This is not a sign that the timing is off internally inside the engine. Usually the timing cannot change internally unless gears break.
What did you see inside that made you think it jumped time inside?

You will also need to carefully adjust the valve lash to minimum specs, especially the intake valve. (most ACR's are on the intake valve and if the valve lash is out of spec or too much clearance the engine will be hard to pull through the compression stroke. Usually the valve lash is set at 1/4 inch past TDC. (or 1/4 inch ATDC (After Top Dead Center of the piston) Most generally the valve lash is .003-.005 cold.

Is that rig electric start?
Reason I ask is I've seen hard to rope pull start engines that would start up ok using electric start.

I really suspect from your description that the unit just needed a new flywheel key and the valve lash adjusted to minimum specs. Valve lash is easily adjusted on a OHV. See youtube for such.

You can find torque specs on-line. (go by the size of the crankshaft nut.
(stud size of the crankshaft)
Most generally 55-60 foot lbs for up to a 25 hp small engine.
Do not use a impact wrench for the tightening torque.
I was able to pull the cord a couple of inches at a time. After doing this three or four times, I was then able to get one full pull, without the cord snapping back, which would start the engine. Also, with the spark plug removed, the cord pulled freely.
Inside, the alignment points were 1 cog off. I'm not sure what the definition of shear is in this context. The key wasn't broken or bent chipped or damaged in any way. However it was shifted 1/4 of its length forward in the slot. By forward I mean from its normal, fully seated position. Putting the key back in place didn't change anything. I was able to do what I described above before and after adjusting the key.
Yes it has electric start but I lost the key and therefore I'm pull starting it.
And I am not familiar with the acronym ACR please elaborate
 

shadetree#1

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One cog off.
Usually a engine will not even run one tooth off and especially come up to speed and carry a load and especially being a generator engine. Make sure you get the cogs right before buttoning it up.
The reason I asked about electric start is some of them emergency gens, especially 10 hp and up are really hard to rope crank in cold weather. (and requires a good battery, sometimes a small lawn tractor battery in cold weather will not crank them and being off grid to keep a battery charged may require jump starting from a vec battery.
You might want to consider taking the key switch to a locksmith and get a key made so as to have easier electric start cold weather cranking since you are off the grid.
UP/down flywheel key won't change timing. I thought you were indicating the key was partly sheared sideways which happens sometimes.
Strange that it is one cog off from the FACTORY.

You can review the operation of the ACR on-line. ACR when correct releases some compression for easier starting and not hanging on compression stroke like you describe. Automatic ACR is critical of correct valve adjustment, especially on a OHV engine. The ACR is usually built into the cam and slightly opens USUALLY the intake valve JUST BEFORE the piston is at TDC. (but can be on the exhaust valve)
Do you know if your engine is a Honda, Briggs or what make????
If you see any engine model, code, etc, post them. We can then get give you more logical precise repair/troubleshooting info instead of just ball park help. The gen model you listed did not help me to get engine info.
 

Daniel 3721

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I'm having issues with starting my portable generator. It pulls easy with no sparkplug.
I removed the valve cover and clean carbon buildup out. I removed and cleaned the carburetor. The spark plug is gapped correctly and so is the (I think it's called) magneto on the flywheel. The flywheel key, which is a half circle key, was slightly out of position. I removed it and put it back correctly and I'm still having issues.
If I slowly pull the pull cord a few times, it will pull start it. does anybody have any ideas? I live off grid and this is my source of electricity. I appreciate any help.
Update
I'm still waiting for the gasket kit.
Someone asked for the model number. On the block is stamped;DHLG225. Then under that, between two stars is, 17100702508. Duro Max xp5500eh dual fuel generator.
 

StarTech

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DHLG225 by CHONGQING DAJIANG POWER EQUIPMENT CO., LTD

Most likely you will not find any service info on the engine. About all you can do is go by a standard screw torque chart and figure which screw sizes you have.
 

Daniel 3721

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Joined
Oct 26, 2022
Threads
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Messages
33
One cog off.
Usually a engine will not even run one tooth off and especially come up to speed and carry a load and especially being a generator engine. Make sure you get the cogs right before buttoning it up.
The reason I asked about electric start is some of them emergency gens, especially 10 hp and up are really hard to rope crank in cold weather. (and requires a good battery, sometimes a small lawn tractor battery in cold weather will not crank them and being off grid to keep a battery charged may require jump starting from a vec battery.
You might want to consider taking the key switch to a locksmith and get a key made so as to have easier electric start cold weather cranking since you are off the grid.
UP/down flywheel key won't change timing. I thought you were indicating the key was partly sheared sideways which happens sometimes.
Strange that it is one cog off from the FACTORY.

You can review the operation of the ACR on-line. ACR when correct releases some compression for easier starting and not hanging on compression stroke like you describe. Automatic ACR is critical of correct valve adjustment, especially on a OHV engine. The ACR is usually built into the cam and slightly opens USUALLY the intake valve JUST BEFORE the piston is at TDC. (but can be on the exhaust valve)
Do you know if your engine is a Honda, Briggs or what make????
If you see any engine model, code, etc, post them. We can then get give you more logical precise repair/troubleshooting info instead of just ball park help. The gen model you listed did not help me to get engine info.

DHLG225 by CHONGQING DAJIANG POWER EQUIPMENT CO., LTD

Most likely you will not find any service info on the engine. About all you can do is go by a standard screw torque chart and figure which screw sizes you have.
 
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