Lloyd 
Ihve had great results with a product called solution one . Got it at the
local
 detailing /auto paint store .
Spray it on let it soak a while (10 to 15 min. ) rinse it off w/ low pressure
water .
With  190k my moter was real dirty so I did this twice in about a week .
Looks just like new .
Usual disclaimers 

mike 85 westy