Valve Adjustment

[ray1933]

Two fold question here. Does the motor have to be cold to do the adjustment.

Also is it normal to change the gaskets each time the valves are adjusted.

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95 3/4 4x4 5 Spd K&N Air Filter 100,000
Ride Rite Air Overloads
10 1/2 Cabover Camper

 

[Joe G.]

Do the adjustment with the engine cold.

The gaskets are really good gaskets so you can use them over. Mine are the originals and I have 154K miles on my '95.

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Joe George
Eureka, CA

'95 2500 CC auto 4X4,3. 54,Combo EGT/boost guage,custom switch panel,PacBrake,TST #5,BD valve body,Automatic motorhome steps on both sides,Foldacover hard bed cover,Cummins chrome kit,Black steel grill guard,Front hitch receiver

 

[ray1933]

Thanks Joe G.
How hard is it to do the adjustment yourself and what are they set at.

 

[Joe G.]

The service manual says . 010 for the intake and . 020 for the exhaust. I have heard . 018 recommended for the exhaust. Cylinder #6 is a PITA to do since you have to lay on the engine to get to it. #5 is bad too, but not that bad. You can do half of them with #1 at TDC and the other half with #6 at TDC. I don't have my service manual handy so I can't say which ones are done for each. If you don't have a service manual you REALLY should get one. It's a bargain if it was twice the price!

 

[ray1933]

Where can one get a manual ?? at a decent price. GENO's

 

[Joe G.]

Ya get them from Dodge. The after market manuals aren't worth the paper they are printed on. Kind of expensive, but when you condsider what a trip to the shop to get something done like a valve adjustment costs the thing pays for itself right away. Like saving one trip to the shop will do it.

 

[1tuffram]

I also supplemented my factory service manual with a B-series service manual from Cummins. If memory serves right the Cummins manual was spendy also (around $50 or $60), but worth the price. I tend to like the Cummins service manual, tells ya which size wrenches are needed, torque values and has better illustrations in my opinion.

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'95 2500 SLT 5 speed 4x4

 

[Turbo Thom]

When you get no. 1 at TDC adj. the tight ones. Same with #6 but don't do ti without the manual. You need a map and that's it.
Good luck.
Preston

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96 3500 Black 5 speed turbo diesel, SLT, with US Gear overdrive, Rhino liner, Reese 15,000 lb. fifth wheel hitch, US Gear de-celarator exhaust brake, muffler elimination kit, Amsoil lub. , with other goodys on the way.

 

[radixr]

There is a step-by-step description of the 12-valve adjustment procedure in Issue #29 of the TDR (page 44). I discovered that you can rotate the engine (albeit very slowly) by using both hands on the crankshaft damper. You need an assistant to tell you when you are close to top dead center (which is all you need to be). Hope this helps. #ad

 

[DavidGardner]

You can also rotate the engine by using a 22 milimeter 1-2 inch drive socket and breaker bar. Just remember to rotate the engine clockwise when viewing from the front of the truck. If you try to rotate it counter clock wise the big serpentine belt just slips
I did mine the last time by reading the TDR article mentiond above. Oh by the way go to cummins and buy six of the little O rings that go on the valve cover bolts. They are cheap (no kidding) and could save you an oil leak down the road. Hope this helps.

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95 slt auto,bd exhaustbrake, TST 230/605 plate K&N airfilter, primelok fuelfilter relocator. Who say"s six in row don"t go?

 

[1tuffram]

Couple of questions:

1) what is the "ideal" engine temp when adj the valves? The service manuals say when engine cold, less than 60 C/(140 F). Do they say this so you won't burn yourself? I was told by a diesel mech normal engine operating temp is ideal temp, problem is when turn engine off it starts to cool, so would not be able to set all valves exactly the same. I have tried adj valves with both engine cold and warm (plug block heater in night before and leave plugged in until finished). I think I get better results when keeping engine warm by block heater.

2) When using feeler gauges how do you know when lash is adj properly? Manuals say "when some resistance is felt" This seems pretty subjective. Sometimes I adjust so it's hard to get feeler in or out of valve and other times more "loose". Only difference I've noticed is when set more on the loose side there tends to be more "clatter" when engine shut-down. Can adj valves too tight cause pre-mature wear? I know there is concern of valve popping to far in cylinder and bumping piston (which is why I stick with the recommended 0. 01" and 0. 02" clearances). Just sometimes I adj a little on the "tight" side with these clearances. Is this a bad thing to do?

I would like to hear anyones opinions.

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'95 2500 SLT 5 speed 4x4

 

[ray1933]

Thanks for all the good information guy's. I dug out Issue 29 and with those instructions
will give it a try myself. #ad


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95 3/4 4x4 5 Spd K&N Air Filter 106,758Ride Rite Air Overloads
10 1/2 Cabover Camper

 

[illflem]

You can also find good instructions if you click TDR Homepage at the top of this page then go to Feature Articles.

 

[samb]

You should adjust the valves when they are cold because they expand when they heat up. If you adjust to tight they couse remain partly open at operating temp and this would burnva;ve seat.
SamB



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97, Lamanie SLT, clubcab, driftwood, 3. 5 spicer 70 rear axle
96 Coachmen Royal 285rk 5th wheel, 11,000 #

 

[radixr]

1tuffram,

My thoughts on your questions:

1. I agree that, ideally, adjusting the valves at normal operating tempeature would be best. But since this is impossible, the next best thing is to do it when cool. Your idea of leaving the block heater plugged in sounds like a good idea if the valve train is no more than warm to the touch. Clearances are different at normal operating temperature (how much, I don't know). I'm sure the . 010" and . 020" specs are adjusted for the change.

2. If the . 010" gage has some resistance, if the . 009" gage is loose and if the . 011" gage won't go, you are right where you should be. If you are on the tight side by . 001" or . 002", I wouldn't worry about it. I don't adjust mine unless they are out by . 002" either way.

 

['956Wheel]

SamB is sooo right, adjust them cold to specs. ,(. 010in/. 020ex) and she will run smooth. The big book says cold taking expansion into consideration... not to keep you from getting burned. Its easy, the b**ch is that timing pin... once you got that mark the crank pulley and you got it made #ad


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9535hundred

 

[Piers]

Put the engine on #1 compression stroke, use the timing pin to locate this the first time then mark your harmonic balancer. Set the first 3 valves, skip 2 valves, set 2 valves, skip 2 valves, set the next valve.
Rotate engine 360 degrees, until your mark lines up again, now you will be on exhaust stroke of #1 cyl. , compression stroke of #6 cyl.
Skip the first 3 valves, set the next 2 valves, skip the next 2 valves, set the next 2, skip the next valve, set the last 2.

** ** ** ** ** ** pretend 6 cyl. motor

TDC of # 1 cyl. on compression stroke both valves will be loose, both valves on # 6 cyl. will be tight.

First sequence with # 1 cyl on compression
* = set
! = skip
1 2 3 4 5 6
** *! !* *! !* !!
Second sequence rotate engine 360 degrees both valves on #1 cyl. will be tight, both valves on #6 cyl. will be loose.

!! !* *! !* *! **
intake . 010 exhaust . 020
Hope this helps.



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Piers, BD engine R&D

 

[C Schomer]

I set mine too tight the first time! Mr. Cummins lost power and sounded like it had a cold! The feeler gauge should slide without bending. It doesn't take much to push 30lb. springs down and be too tight! Craig

 

[ray1933]

Piers,, i liked your discription of the 6 cyl engine. #ad
I printed that post out, so that along with the magazine should should allow me to get the job done and save $100. 00
bucks that my **** star dealer wants for the job. I'm sure I will fing out how much of a PITA number six is. I may try laying a small peice of clean plywood on top of the engine
to lay on. Thanks again Guys!!!!!!!!!!

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95 3/4 4x4 5 Spd K&N Air Filter 106,758Ride Rite Air Overloads
10 1/2 Cabover Camper

 

['956Wheel]

Ray, just do it, and you will know its done right #ad
#ad
... no darn Bull$hit and potheads working on you precious CUMMINS! Take your time and slide that feeler over and over, the cool thing about adjusting the diesels is they really sound and feel better! #ad


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9535hundred