Idler pulley mandatory update

All Viking engines now must use this idler pulley.

(Unless your engine was delivered after the 2014 model year)

Idler Pulley 

Gates 36026 Drive Belt Idler Pulley

Use 12mm washers or fabricate a spacer to align pulley with crankshaft pulley.  

Tape a 0.090 spacer to the crank pulley to compensate for the lip on the idler pulley.  The use a straightedge firmly pressed against the crank pulley + spacer disk to align the idler. 

See 0.090" shim on crank pulley in order to compensate for the idler pulley fatter lip.  

We ordered THESE 12mm washers - click on this

Using the original bolt, we were able to add a single washer on the aft side of the pulley, 5 wahers between the pulley and the engine an no washers but thread locker on the nut side.  If you would rather have a washer under the nut, turn the bolt around.

Be sure to add a washer here and do not support the pulley on the built in sleeve but rather the inner race of the bearing.  

Max and Don made their own alignment tools 

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  • Hi Robert. Instructions are above. Do you have any specific questions? Keep in mind every engine is not exactly the same as time went by. On some the attach hole might be 10mm, some 12mm and some might have a tapped hole. However, the installation is generally the same. If in doubt, ask here or get a trained mechanic to assist.
  • Could someone please direct me to the step by step instructions for installing the gates pulley? Thanks.
  • Marvin W Miller October 23, 2014 at 12:05pm
    Replaced idler pulley with gates pulley. Menards has chrome steel spacer that fits perfect between pulley and engine. Part #87016 1/2 by 1/4 steel spacer.
  • I think the Gates pulley is great, and the instructions are straight forward.
    My problem is that I cannot locate in my area 12mm washers in varying thicknesses (they are all about 1/8"thick). This makes it difficult to get the spacing needed to get the pulley groves to line up.

    With all due respect this is just half a solution. Anybody out there with a metal lathe interested in fabricating and selling a proper spacer? I was finally able to drill out and use a thinner washer, but I would really love to have a proper, machined spacer.
  • Thanks Jan, that is a big help for us with the engine installed.
  • I added some instructions above to get the pulley to align.
    The important part is to get the grooves to align.
    Thanks for checking carefully and making info available. That is what the forum is for.
    The reason I am being careful throwing a spacer dimension out there is because the attach point for the pulley has changed a couple of times.
  • Exactly what I found. Aligning the pulley faces doesn't align the belt grooves.
  • Be careful, there is a lip on the aft side of the idler pulley - but none on the crankshaft pulley! Aligning the aft surfaces with a straightedge does not align the grooves where the belt rides. So far I have seen three different spacer dimensions quoted, all different from each other!
    I can envision an alignment with the old Honda cast iron crank pulley perhaps being different as well.
  • Jan I installed the new ( Gates) idler pulley today but the outer edge of the pulley is offset differently than the original Viking pulley in regards to the belt groves. I made the spacer so that the top of the first (aft) ridge for the serpentine belt is the same distance as the crank pulley. My spacer ended up being about .405" I made a jig out of AL that rests on the back of the engine mount. I think this is the correct way to do it rather than a straight edge across the pulley faces. Any comments?

  • Just click on the words "idler Pulley" in the original text above
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