right way to do it wrong

jessewmcgregor · 03-31-09, 08:54 AM

hello gurus..
i am about to attempt my first valve adj. on my 88 fj62. per the fsm and here on mud i know that the engine needs to be hot for a proper adjustment but i know this being new to me the engine will be cold well before i get through it. i have read a couple of places that people set the clearance a little tight on a cold engine to compensate. i would like to know how tight. the fsm suggests .20 mm intake and .35 mm ex. how much should i adjust those values. thanks

tonkota · 03-31-09, 09:06 AM

Set them LOOSER if cold, the metal will expand.

IIRC several guys here have set them cold using the hot recommended clearance. I usually add 0.001" and then adjust, but then they "seem" too loose.

Have fun!

dgangle · 03-31-09, 12:46 PM

Good advice. Be sure to check them again once hot to get it dead-nuts on.

fowldarr · 03-31-09, 01:02 PM

Not that hard to do it hot. I took a couple of practice runs. Tearing it down to the valves, to make sure I knew where all the bolts and latches were, then just did it. When I got down there it was still plenty warm.

Theycallmenica · 03-31-09, 02:03 PM

Easy to do if you take your time and double check everything.

tonyota · 04-01-09, 08:29 PM

I have always done mine cold & set them to factory spec... Cold as in a 70 degree day in spring ...always runs strong & quiet.

2mbb · 04-01-09, 08:59 PM

Last time I adjusted my valves, I did the cold according to the excerpt in this post: IH8MUD Forums - View Single Post - 2F/3F hot/cold valve set. I added 0.002" to the valve clearance. All the clearances measured OK--I did not have to adjust any of the valves. It had been 20K miles since I last adjusted the valves hot.

Here's a table I use to help me adjust the valves. I set the engine to TDC on the #1 compression stroke, then I check/adjust the exhaust valves indicated with an "a"; counting from the front, valves 1, 5 & 9. Then I check/adjust the intake valves indicated with a "b". Then I rotate the crank 360 degrees back to TDC on the #1 exhaust stroke. Then I do the "c's", then the "d's". Doing the intakes and exhausts in sets of threes helps it go faster, which is good if you're trying to do it hot.

I also find that a "step" or go/no go feeler gauge is handy. This is a feeler gauge where a distance back from the tip the gauge step up .002". If the tip goes in but the step-up doesn't then the valve is adjusted properly.

jessewmcgregor · 04-02-09, 07:24 AM

wow thanks for the posts this is just what i needed..2mbb, where did you get the step feeler that sounds like just the thing to keep me honest.

Lugal · 06-21-09, 07:47 PM

2mbb's chart should be added to the FAQ. I adjusted my valves for the first time ever today, and his post made it easy. FWIW, I checked w/ the engine cold, and most of the clearances were right on the .002" over mark. A few were a bit too tight, so I set them to the cold specs too.