12 valve
 

I am new to this web site. I have a 12 valve cummins. On somedays when the temperature is just right my truck will run perfect. When it gets to hot or to cold the truck will act like it lost its power. What could be wrong with it?

Does it seem to happen during the summer and winter months,or all year round?:humm:

Mainly when it gets really hot and when it gets about 50 degrees otuside. It runs great when it is about 65 to 70 degrees outside.

diesels do not like the cold so, that could be a small warm up issue. All motors loose power when its hot. I like towing at night because its cooler and power and mileage go up:U:

mine runs good when its hot or warm i get 25 miles a gallon running around town,when its cold my tranny dont shift right so my mileage goes down

my 12v HAS to warm up for a solid 15 mins or it is a dog. it is a good practice to do so eitherway, on any diesel.

as far as power and fuel economy on a hot day, keep in mind air density plays a big part in a boosted engine's performance.
hot air is inefficient and less dense.

down here we mostly drag diesel's at night, as +100* air temps during the day can cramp our style:ouch:

ive noticed up here an 90* days my cummins losses just a tad bit of power but not enouph to totice as for cold i wait till the thermostat pops and driver like i stole her but i also have a crap load of performance upgrades that may play a small roll in that

Come on up where its cold and see how crappy these things run. I dread winter.

winters sucked up north, thats why i moved to texas, only 2 weeks of crappy cold then back up the charts we go!!!:viking:

granbury. its nice up there. days are nice right now, but gets stick and cold over here in the tyler- carthage aread

my truck hasn't been off in about 4 days so it wouldn't even know its colder up here lol:ouch:

Where is a good place to get a good set of head bolts and a head gasket for the 12 valve cummins?

How about one of our many site sponsors?

when upgrading your head you will be going from head bolts to head studs.

here is a link for the ARP head stud kit. ARP makes the .030 head gasket as well.
ARP 12MM 94-98 Dodge 5.9L 12 Valve Cummins Diesel Cylinder Head Stud Kit 247-4203

i love the days we get to 0 let the truck get up to temp then pore the edit to it and let all the ricers see what my huge truck can do. i can drift corners in the snow better than they can with the cars and e-braking it, although you can hardly see me with all the black sooty diesel smoke

What is a good air filter for the 12 valve? I already have the intake I just need a good filter.

IMO the AFE with progaurd 7 media is the best in filtration. if your looking for a good filter, but it is a few more bucks thatn the others, but to me truly un "dusted" air is worth the price.

i drive up and down oilfield coleche roads all day and when i pull my filter for service there is barely ever even a trail of dust i can wipe away from the torque tube with my finger.

others to look at are S&B and the AFE dry filter.

the key here is to stay away from K&N!!!!!!!!!!!:ouch::moon:

What about the BHAF filter that what I've been running with good service.

Why use a BHAF when you can have an AEM Dryflow or AFE Prodry S??



Seems like a waste to me that you just throw the BHAF away. Get a WASHABLE filter.

ALSO, some of the big power guys will tell you that the BHAF's will collapse after a while. depending on which on you use. i am pushing roughly 600hp at the flywheel on my CR and my afe has hardly any crush:c:

my 12v had a NAPA BHAF on it when i got it and it was half caved in from being wet when driving in the rain :ph:

Yes, the BHAF doesnt handle moisture very well. Unless you run a prefilter/cover

i agree with staying away with the k&n filters they dont work i lost gas mileage and the one i have now i always have to clean it ill be gettin a afe intake very soon

You dont necessarily need the whole intake. If you have some inginuity, you can fab something up.

Where can you find a set of push rods for a 12 valve cummins?

do you want stock or chromally

k&n filter red

It does not really matter.

a set of chromally push tubes are about $200

My truck is pouring a steady stream of oil down the side of the crankcase vent tube. What is the plate called that the tube goes in and how do you change it? What all do you have to remove to get to it?

i think its called the tapet cover for the push rods but ive been wrong before

When you remove the fuel pump do you have to refill it with oil.

i did just for safety when i put mine back on just like changing the oil put oil in the filter before screwing it on. it definatly wont hurt it

the pump or the filter?

pump

it wont hurt

I had to replace the tappet cover on my 12 valve. When I put it all back together the truck set and idled perfect. When I drove it about a 1/2 of a mile, it started blowing out white smoke and it could hardly pull itself. I thought it may have run out of fuel so I put some in it and it still won't start. I have tried everything. I also just did a head job on it. Can someone please give some advice?

It smokes a lot of white smoke and I can get it to start with starting fluid, but it will not run. If you push the pedal to the floor it will crank and rev up but will not stay runnig.

sounds like its not getting fuel, crack a few injector lines while cranking and see if its spraying out fuel, be carfull dont put any body parts next to it :ouch:thats pressureized to 25,000psi i beleive then again ive been wrong before

We have cranked the lines and fuel has come out, but it still will not run. I believe the transfer pump is going out.

it might be but if fuel is going threw the lines then it should be starting even if its low fuel pressure:humm:,

How many miles?

I dont think fuel pressure is the problem here. I see in previous posts that youve had the injector pump off. Is that true? If so, I would start there.