Help with valve adjustments. Tb42.What the hell is going on

[jamied]

Ok so decided to have a go at adjusting the valve clearance on the old girl. Followed the manual step by step and made the adjustments in the correct sequence. I set them to .38 mm as per the specs. Put it all back together, got it running and went for a drive. It ran like a complete dog. Took the rocker cover back off and double checked everything and it all seemed fine. After checking everything else and finding no reason for it I started again but this time set the clearances to .48 mm. Is now running heaps better but still not perfect so I've come to the conclusion .38 mm clearance isn't right for my patrol. I have no idea why and want to know how to work out what they should be set to. Any ideas??

[threedogs]

Is it ,38 MM or .38 thou, you may also be 180 degrees out
These are specs when hot
Cold the clearance is .20mm inlet/exhaust
that will make a huge difference

[patch697]

Check this thread out mate its got all you need to know to do the job.

http://www.nissanpatrol.com.au/forum...pet-Adjustment


A quick question while im at it.... When you do an adjustment, how dose the feeler gauge fell??.... Is it tight, firm or just neat to get in between the valve stem & rocker?

You can throw your adjustment out by a good whack if the feel is to tight & the feel is not even throughout all adjustments.

It only needs to feel neat mate.... Just enough resistance or drag to put a little bit of pull on the gauge when removing it & thats all. & always remember to recheck your gap settings after you tighten the adjusters lock nut.

[jamied]

Its defiantly not 180 degree out. I made sure of that and it is .38 mm. I even double checked the feeler gauge using the micrometer. The feel is as far as I can tell pretty right. It's not grabbing the gauge hard but just enough so you can feel slight resistance when moving the gauge. I've double checked everything more than twice. That's why it just doesn't make sense.

[threedogs]

Do inlet /outlet at .20mm cold, if 100% look elsewhere why running like a dog?
was it rough before?? might be leaky vacuum or fuel lines.

[jamied]

No it was running fine before. Just a little bit of a Tap which is why I thought I would do them. By backing them back off to .48 mm it greatly improved how it runs who's its deffinatly to do with the adjustments. Just seems to me like the specs given arnt correct for some reason

[Bob]

Is your Truck EFI and if not take off the Tappet Cover and adjust Tappets with Motor running,
Might require two people One to adjust the clearances and the other on the Feeler Guage.
Have done this many a time on the older Motors.

[Benno7]

Is it on lpg ? I believe they should be set different if it on lpg. correct me if im wrong

[jamied]

It not LPG and its carby.

[threedogs]

Do you think someone has fitted a towing or gas cam in it??
Some people call them gas cams, but just more torque for towing

If this is the case take Bob's advice

By opening the clearance up is telling me it has larger lobes