Planning on working on my wife's 07 is250 this weekend because the car is about to reach 100,000 miles. I'm going to be changing her sparkplugs so I thought while I got the intake manifold off ill clean the intake valves from carbon buildup by walnut blasting it.


I have a remote control starter switch to turn the engine over to close the intake valves but it's hard to get to the starter since its underneath the left headers. So since i cant get to the starter im planning on turning the 22mm crankshaft bolt by hand to open and close the intake valves. Im going to take out all the sparkplugs too so i wont buildup any compression in the chambers. But before turning the crankshaft, do i have to remove the serpentine belts or could i leave them on while turning the engine? Should i turn the engine over while in park or neutral? Is turning the crankshaft the best option or is there a easier way to crank the engine over to open and close the intake valves?


This is going to be a one man job so im trying to find out whats the easiest way. I would like to hear other peoples thought and opinions on how to turn over the engine using the crankshaft.


If this all goes good ill post up the diy after im done.


Thanks

 

I'd just rotate the assembly at the crank and do nothing else. The trans position won't affect it any I wouldn't think.

Let us know how it ends up; you'd be the second I've read about doing the walnut blasting to break-up the carbon build-up.

Good luck!

 

Thanks for the reply. I definitely let you guys know how this comes out. My wife car just started throwing out the shudder and rpm dipping when coming to a stop symptoms and took it to Lexus and was told that we were out of the Lexus care package by a month. Talk to corporate and they said they couldn't do anything since I was out of date. Lexus wanted to charge me $3500 for top engine clean.

Since then I've been running Seafoam every month thru the vacuum line and adding it to the gas tank and running it at full throttle for the past 3 months. The first time I Seafoam the car the rear bumper was cover in black nasty stuff from the engine which I believe was carbon buildup.

 

^Let us know how the carbon build-up looks in the chambers BEFORE hitting it with the blasting so those thinking of using Seafoam can see what it does or does not do after three applications.

Yes, that build-up on the bumper were carbon particles being blasted out of the exhaust.