Engine/Transmission (1998.5 - 2002) Valve adj.

[SWEdholm]

With 125K now showing, what is the recommended intake and exhaust clearance. No real problems, but have not had any adj. since about 30K. I think I want to see where they are and adj. if necessary to what you experts seem to think are the right/correct settings.

 

[RobertP]

well the recommended valve lash is int . 10 and exh . 20





Robert

 

[SWEdholm]

Thanks Robert! Is there any advantage to going . 08 and . 18??

 

[Diesel Nut]

No. You are supposed to do the adjustment on a cool motor, and if you adjust them too tight when it heats up and expands you could inhibit the valves from closing all the way ad wind up with misfires.



There is a window, but . 010 and . 020 is about perfect I think.



You know the procedure?

 

[SWEdholm]

No I do not! Is it timely enough to explaine or could you lead me to it?

 

[RobertP]

i would not recommend 8 an 18 for the same reason.

 

[Diesel Nut]

VALVE LASH VERIFICATION & ADJUSTMENT

NOTE: To obtain accurate readings, valve lash measurements AND adjustments should only be performed when the engine coolant temperature is less than 60° C (140° F).

The 24–valve overhead system is a “low-mainte-nance” design. Routine adjustments are no longer necessary, however, measurement should still take place when trouble-shooting performance problems, or upon completion of a repair that includes removal and installation of the valve train components.

(1) Disconnect battery negative cables.

(2) Remove cylinder head cover (Fig. 12). Refer to procedure in this group.

(3) Remove the fuel pump gear access cover

(4) Using the crankshaft barring tool #7471B, rotate the engine and align the pump gear mark with the top dead center (TDC) mark on the gear housing cover (Fig. 14).

(5) With the engine in this position (pump gear mark at 12 o’clock), valve lash can be measured at the following rocker arms: INTAKE 1–2–4 / EXHAUST 1–3–5. Measure the valve lash by insert-ing a feeler gauge between the rocker arm socket and crosshead (Fig. 15). Refer to the Valve Lash Limit Chart for the correct specifications. If the measurement falls within the limits, adjustment/resetting is not necessary. If measurement finds the lash out-side of the limits, adjustment/resetting is required.

VALVE LASH LIMIT CHART

INTAKE

0. 152 mm ( 0. 006 in. )

MIN.

0. 381 mm (0. 015 in. )

MIN.

EXHAUST

0. 381 mm (0. 015 in. )

MAX.

0. 762 mm (0. 030 in. )

MAX.

If measured valve lash falls within these specifications, no adjustment/reset is necessary. Engine operation within these ranges has no adverse affect on performance, emissions, fuel economy or level of engine noise.

(6) If adjustment/resetting is required, loosen the lock nut on rocker arms and turn the adjusting screw until the desired lash is obtained:

² INTAKE 0. 254 mm (0. 010 in. )

² EXHAUST 0. 508 mm (0. 020 in. )

(6) Tighten the lock nut and re-check the valve lash.

(7) Using the crankshaft barring tool, rotate the crankshaft one revolution (360°) to align the pump

gear mark to the 6 o’clock position in relation to the TDC mark on the gear housing cover

(8) With the engine in this position (pump gear mark at 6 o’clock), valve lash can be measured at the remaining rocker arms: INTAKE 3–5–6 / EXHAUST

2–4–6. Use the same method as above for determining whether adjustment is necessary, and adjust those that are found to be outside of the limits.

(9) Install the cylinder head cover

(10) Install the fuel pump gear access cover.

(11) Connect the battery negative cables.

 

[SWEdholm]

Thank you !!!

 

[PPettit]

Diesel Nut,

That was a great post. I read it 20 min after I did the valve adjust on my '01!

A couple notes.

1. The breather on the front of the motor screws off. It does not feel like it will but it does.

2. Reaching the valves for cylinder #6 is a B!@#$. I had to lay across the battery and stock air filter box to get at it.

3. I have a 5 gal. keg of home brew in the shop and I highly recommend using it sparingly until after the job is done!



This is a fairly simple job to do and if you have put it off for 120K miles like I did you will notice the engine runs a little smoother afterwards.



Phil

 

[Diesel Nut]

5 gal keg? Where in Or are you, we are going to see mom and dad in Roseburg next weekend! :-laf

 

[Joe Mc]

Crank Barring Tool. Good luck trying to locate one and when you do be prepared to pay. My "Crank Barring Tool" = socket and ratchet on the alternator bolt. When I first did mine I asked here about the "barring tool" and was told what I just suggested - guess what? it works. Oh, I agree 10 & 20 - you can bend pushrods if too tight - not cheap.

 

[TimBrunett]

I did my 01 valve adjustment about a week ago using the instructions I found here. My thanks to those who have made it so easy for me to save $125-165 it would have cost to have it done. My thanks also go to Andy at Geno’s who helped me over the phone. Like most everyone I don’t have a barring tool so Andy suggested I using the alternator nut to turn the engine over with the belt and it worked fine. When I first started I recorded all existing clearances. The intakes were . 012-. 013 and the exhausts were . 022-. 023 so I set them at . 009 and . 019. The job took me about 3. 5 hours because I checked everything 2 or 3 times. The engine does seem to run a little smoother but it’s hard to tell. In any event, I have a baseline and more importantly I now have the experience of doing it myself, I saved a few bucks and I have that satisfied feeling.