Cat Engine Overhaul

the reason I asked is you may have a broken ring if you have a lot of blowby and oil slobbering out the blowby tube. another thing to look at is the air compressor had one pumping air into the crank case a while back. changed compressors and solved it. if you do a lot of idling that isn't good on a fresh overhaul. you can (polish the liners) and that will cause oil usage.

 

www.partinfo.co.uk/docs/29

 

It's like when converting mbn into 6nz.

 

Has anyone tried the cac from PDI and if they have does it really lower ur egts by 150*-200*? Just thought this might be a route to go to try to cool down my egts.

 

I haven't read all 3 pages, but mine uses Rotella like it's going out of style, inframe done last July. I started changing my own oil, using BradPenn semi-syn 15w-40 and the oil use COMPLETELY stopped... about 2 quarts in 15k miles now. Just my two cents' worth.

 

it is a duralite cac they sell. if you get the larger one, yes it does cool better. you will have to modify your lower cac mounts about 6 inches lower and lengthen your a/c brackets to make it fit for a w900L. nothing a weekend and a few cold ones will make it go easy! egt's maybe but it will lower your air intake temps by about 40 degs.

 

Where do you usually run for rpms? Just for the heck of it, next time it gets up there drop 1/2 a gear and watch the difference. I am guessing you will find, as I have, that it drops a whole bunch. I hope you can get back on this, if you have a chance, I'm guessing if you were pulling 8 axles instead of 6 you'd be running very similar to me.

 

BullDoggin I am guessing this BradPenn semisynthetic oil is something local. The Brad being Bradford and the Penn being Pennsylvania. Could you enlighten us on this oil? Thanks

 

I do have a 7 axle rig as I got a lift on the truck and I do try to keep the r's up when going up hill maybe around the 16-17 range and that does help. I just don't feel comfortable with the temps past the 950* to 1000* mark. I read a post on another thread that the cats can withstand 1100* all day long with stock parts, but when u start to modify things change. I have come along way with this engine. When it was a stock mbn I was freakin out when I would pull a hill I would easily hit 1150*-1175*. But when I read that all these other folks never pass 900*-950* it makes me want to know why I can't do the same. Maybe it is just the weight, ambient temp, and wind conditions. I don' know.

 

I think you're right on all 3 of those things. I have observed that on a cooler day, say 60F instead of 80F, egts will be much cooler. Head winds too, I can easily hit 900 running empty, but into a headwind, in 18th at 1400. And as far as the weights, for sure, there are several who run lighter gross weights, and then for sure they aren't going to have any problems with temps. I must admit I never used to pay much attention to the pyro when it was a stock mbn, set the cruise and let er go. Then about the time I started making changes, the pyro quit, and I finally ended up putting in an aftermarket digital, which btw, is the only way to go for a quick glance and very accurate, instead of trying to read the stock one in it's vague analog method. IMO anyhow. If you come across any other tips please share, I'll do the same.