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Hustler z losing power

Discussion in 'Mechanic and Repair' started by Billsz28, Sep 26, 2012.

  1. piston slapper

    piston slapper LawnSite Platinum Member
    Posts: 4,240

    Bill...by the looks of your sparkplugs..its probably a leaking head gasket..look closely at the area between the oildrain hole and the cylinder..the reed valves are located between the lifters on the block.
    You probably didn't have any blowby....if you remove any dipstick while the engine is running..its gonna blow oil out...when you took out the dipstick...you lost all your crankcase vacuum . It takes a special vacuum gauge to check crankcase vacuum..

    One more thing to check...was there a lot of buildup on the pistons?
    If so...move the piston to the top of the bore and see how much flop you have in the rings..push in on the top and bottom of the piston...
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  2. Billsz28

    Billsz28 LawnSite Member
    Posts: 70

    Should I be removing the problematic cyl head to examine the condition of the piston or breather valves?

    Would it be more wise to wait until I get this leakdown tester?
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  3. piston slapper

    piston slapper LawnSite Platinum Member
    Posts: 4,240

    Your engine is using oil ..so the headgasket will need to be adressed sooner or later..
    When you replaced the sparkplugs did the engine run good again ?
    If it didn't...you may have a coil problem.
    You can't access the reed valves without removing the heads...one on each side.
    They don't break very often...when they break they use a ton of oil...
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  4. Billsz28

    Billsz28 LawnSite Member
    Posts: 70

    Update...

    Got my leakdown tester which showed negative results for valve/piston ring issues. It showed steady in the green area for cylinder #1.

    It seemed to run better after the new plugs according to the owner. Still using a lot of oil. I had the machine in the shop today and went ahead and replaced the head gasket on
    cylinder #1 which looked like it was leaking on the outside of
    the head (this is the cylinder with the oil soaked spark plugs).


    Breather Reed looked ok. Piston did not have much flop at all.
    Tons of buildup on the piston though as you can see in the
    photos.


    Slapper, when you do head gaskets on these motors do you
    have the cyl head machined for flatness as is normal when
    doing head gaskets on cars?

    The gasket I took off of cyl #1 did not appear to be in as bad condition as I was expecting. What do you guys think from the photos? Thanks

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    Last edited: Oct 7, 2012
  5. Dave

    Dave LawnSite Senior Member
    from RI
    Posts: 315

    that head gasket is junk, also do check the head for levelness, run it on some 120 grit ,on a flat surface until you see scratch marks from the sandpaper across the whole head
     
  6. piston slapper

    piston slapper LawnSite Platinum Member
    Posts: 4,240

    Looks like the head was not torqued properly...leaking between the lifter valley and the cylinder...also the gasket is degraded between the oil drainback hole and the cylinder..
    Clean all the carbon and crud off the piston and head..
    It is always best to resurface the head...be careful..if you send it to a machine shop they might shave too much off the head which may keep the valves partially open...get a sheet of sandpaper and put it on a large piece of glass to resurface the head..
    Make sure you get the new updated headgaskets...
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  7. Billsz28

    Billsz28 LawnSite Member
    Posts: 70

    Ok I torqued the head in 2 steps first to ~160 in/lb then finally to 315 in/lb in the order designated by the instructions. Torqued the rocker arm pivot bolt to 124 in/lb does that sound about right? I did clean up the head with light sandpaper on a level surface.
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  8. piston slapper

    piston slapper LawnSite Platinum Member
    Posts: 4,240

    Rockers should be 100 in lbs...wouldn't want to strip out the threads...
    How does it run now. ??
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  9. Billsz28

    Billsz28 LawnSite Member
    Posts: 70

    Head gasket was Kohler 24 841 04-s is that the updated one? It seems to be running nice now, however it has been raining all weekend so I haven't been able to really check. I put the rocker arm pivots down to 100in/lbs from the 124in/lbs the service manual suggested. It does sound much better. Thanks for the help guys
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