Makes absolutely NO difference how you align them if your spindles have v-groove pulleys and plain v-belts. In fact, if you tried to align them a specific way, after you mowed for only a few minutes the alignment (or "timing") will have changed. If your spindles have "toothed" flat belts and "cogged" pulleys, your blades will need to be "timed" or "phased" according to the OEM instructions. The decks with "cogged" spindles and "toothed" belts have blades that will strike each other if not "timed" or indexed properly (or if the belt breaks or jumps time)

Has V Grooved pulleys and spindles so wont worry then.

Thought that maybe there was a sequence so that the outside blade throws its clippings to the middle blade to the inside blade then out the shoot.

Txs.

I'm pretty sure that this is the worst alignment you can have from a vibration standpoint. As the tips pass each other, they will create a shock wave that will be felt in the deck. Boats and airplanes take measures so that this alignment does not occur. It's been a while since I looked at the manual, but I believe Simplicity recommends a blade alignment that is 180 degrees out of phase.

Hmmm..that kinda makes sense..also any slight out of balancing would be offset rather than synchronized.

Since it really doesn't make a difference , think that's what I'm gonns do. (180 offset)

As mentioned above by mownie, they are NOT going to retain any synchronization, which you attempt. Just put them on and forget it.

You are correct. My Conquest recommends 180 degrees. Take care

tmajor,

Depending on belt and pulley condition along with belt tension, it will take time for the blades to loose sync. Wouldn't it make more sense to start with them out of phase vs waiting on this to occur over time??? My current mower only has about 10 hours on it and it takes considerable force to move the blades independently (holding the center blade and rotating the outer blade).

It might be better to start out of phase. But I doubt that after your first mowing, they'll still be the way you set them up. The other thing, your machine has 10 hours, how about after 100 hours? Also, trying to turn the blades by hand, doesn't equal them spinning at 10,000fpm and hitting a slight snag, like a limb. IMHO

Agreed, the belts on my old murray were so dry that I used belt dressing to keep their grip up when cutting grass that had gotten a little high. But I think the inertia of a spinning blade and spindle would actually serve to keep them in sync unless you hit something substantial (provided they were started under a light load). I think most slippage would occur due to constant loading (such as high grass) and the variation of slippage on the pulleys during the high loading. Nice thread that so far has had nothing to do with cheap machines, great machines or things dug up from the past. In north georgia, we have gone from dust bowl to mushrooms in about three weeks and things really are greening up nicely. Looking forward to the weekend. Sill have to fix the RIO problem with my Broadmoor.

I had a job working after school and weekends at a busy garage/service station when I was 17 years old. We had a customer who requested that while I had his car off the ground for servicing, I should "match" the position of all his tire valve stems to the 6 o'clock position so that it would be easy to check the tire pressure (his car had "fender skirts" over the rear wheels, if you remember those). I complied with his request but have never concluded whether he actually thought the valve stems would stay "in sync" considering the difference in wheel speed between inner & outer wheels in turns, or if he was just pulling the leg of a young "wannabe mechanic".

BUMP for an aging thread :) Can someone please clarify what a 180 degree offset would be for 3 blades? My high-school math isn't razor sharp, but if 90 deg is a right angle (blades perpendicular), wouldn't 180 degrees be parallel, i.e. in the straight line we're trying to avoid?

I have 2 mowers, both v-belt, and my MTD shows blades like (- I -), my Murray manual says nothing about alignment...

Wasted effort. Unless your spindles are timed (with a cogged timing belt - very rare) there is no need to "time" or offset the blades. After 10-min mowing they will be every which way. Makes zero performance difference.

60" Ingersoll/Case deck is timed with a timing belt.

HA! You are correct, the blades have a 90 degree "offset" (one blade 3:00 to 9:00 and the other 12:00 to 6:00) which results in the blades being perpendicular to each other.

And for what it's worth, My Broadmoor's blades are aligned pretty close to this (after 20 hours on a new machine).

Maybe they have been slipping "every which way" and this was a coincidence, but I don't think so. I checked that the blades would all move freely, then held one while I tried twisting the other; it was very difficult to get any movement. Engine-tech, you better doctor those belts or they are going to burst into flames from slipping on the pulleys.

Thanks for the excuse to pull the deck and do a little spring maintenance.