Welcome to the forum. Yes, the little 4bt is a vibrating monster and can loosen bolts occasionally. Especially if they weren't torqued correctly to begin with. Where the cover attaches to the front gear housing is a known leak area. Although there is a gasket for that spot, seems like Cummins recommends a gasket compound instead. I believe all those bolts torque to 18 ft lbs which isn't an extreme amount. A torque wrench isn't an extremely expensive tool and might be a good investment. Thread sealer is recommended on some of the engine bolts, but don't believe it's on those. As to whether the KDP issue was repaired I can't say. About the only way to know for sure is remove the front cover and look. Doing that would require replacing the front crank seal since that can't be reused. Also, there are several bolts behind that cover that are notorious for working loose. Those are supposed to have blue Loctite used on them. The bolts holding the lower crank pulley also use Loctite. Think those recommend the red version which is even stronger. Sometimes have to heat those bolt a little to break them loose. If you knew someone with one of the camera probes you could insert it in the port on the front of the cover and look at the area of the KDP to keep from removing it.

 

On my 4BT when i tppk it out of the bread truck with just over 200,000 miles i noticed some lose bolts and when I did the KDP fix all of the timing housing bolts were lose.
Having worked as a machinist/mechanic in the maintenance field I used the rule we used there "blue locktite on everything if it shakes,rattles or rolls" so every bolt that needed to be re tightened got the internal and external threads cleaned with Brake-kleen then dried and blue locktite applied unless red was required.
When I did my overhaul last year I locktited everything except the valve cover bolts and exhaust manifold bolts as they get so hot that there was no point, I look at it as cheap insurance over the long haul............$.02

 

Thanks for the replies. Look like I spoke too soon- 80 mile round trip today and the leak started back up. Definetly the timing cover, just to drivers side of main pulley where there's a slight lip in the cover bottom and a bolt with a larger head than the others. Going to pick up a torque wrench this week and check the cover bolts (and anything else I can reach for proper torque). It does seem strange that it got worse so quickly.

If that doesn't solve it, I might take a stab at pulling the cover and resealing (plus checking kdp and housing bolts). Feels a little daunting to an amatuer like me, but that's how you learn, right?

Thanks again

 

Also, like Steve said, get yourself a few cans of the brake cleaner to remove the junk in the holes. Spend a few bucks an get you a few bottoming taps of the correct size to run in the holes to make sure the threads are clean.I believe there is a listing of torque specs for the bolts posted on the forum. The vast majority of the external bolts are 18 ft lbs. The crank pulley bolts are different. Should you decide to remove the front cover, replacing the front crank seal will be necessary. When you reinstall the cover, the crank must be totally dry and free of oil. Otherwise the seal will leak. And as I said, RTV has become the accepted seal material for that front cover.

 

Update-

I picked up a proper torque wrench and cranked the cover bolts down to spec. Still leaking badly after the block has gotten good and warm. Seemed like maybe leak was coming more from vacuum pump area. In looking around I noticed a chip out of the timing housing itself, on the backside just where it clears the block under the vacuum pump. When I got home from a drive today I climbed under and cranked my head around to see what looked like fresh oil coming from the chip. I'm thinking it's possible there could be a crack there that's opening up when the housing iron gets hot enough. Maybe damage from the swap, or something else...

Any ideas of possible causes, and a fix? Weld, replace housing, etc? I attached a photo, chip is visible dead center of pic on backside of housing.

Thanks again

 

Can't really tell, but is that a crack or just a seam in the front housing? If it is cracked, it could be welded. Means taking it off along with everything attached to it. Could also be the gasket between the PS pump and front cover leaking or the gasket between the front cover and the block. Lots of possibles there.

 

I had to fix a cracked timing housing about a month ago. It was ultimately caused by not having a support bracket from my vacuum/power steering pump to the block to prevent shaking the timing case up too badly. The bracket also supports the end of the injection pump. Mine was cracked right through and I was loosing about a quart of oil a week and I wasn't having much luck with RTV or other sealers to stop it. I ordered a new 5.9 timing cover off ebay to fix the issue, but its a pain because the cam had to come out to get the timing case off.

 

Yes, not a fun chore to change a front housing. Not installing that little brace for the power steering/ vacuum pump combo is a bad mistake many make. It is absolutely necessary. Sometimes the housing of the vacuum pump will break. That isn't pretty either.

 

Anyone got a picture of this brace and how it mounts? I made one but I’m bracing the power steering vacuum pump to my injection pump and that ain’t gonna work.

 

The support brace is nothing fancy. It's just a simple angle brace. Here's a video by Gould Gear and Electric who is the premier rebuilder of those pump. You can see the brace in their video. Main problem is on the 4bt the injection pump brace is using the same territory so something custom has to be devised. I think some may have welded a piece to the pump brace to act as the support. https://www.youtube.com/watch?v=vJhR48a-9R8

 

It had been a while since I made the brace that runs from the front of my power steering pump up to my injection pump. The injection pump does have a brace that bolts to the side of the block. This brace is slotted to allow for the pump timing. So I should be ok. Thanks for the post.

 

i had a similar issue last summer. i purchased a swapped truck as well, and it looks like the cause of the issue was the welded on bracket to support the ps/vac pump. it looked like the hole drilled in the bracket was slightly off causing pressure on the pump housing. mine failed in a spectacular fashion, and with the replacement we opened up the hole in the bracket with a drill. haven't had a chance to put much more mileage on it but it's been trouble free so far. i attached the photo of my bracket

 

Thanks.

 

Here are a couple pictures of the PS brace I made. View attachment 114682 View attachment 114690

 

Anybody used the hydraulic motor mounts from Lord? I wonder how much they actually reduce the vibration and cut down on loose bolts/unsecured KDP issues?

 

Those engine mounts are probably the best for a 4bt. However, the engine mount controls vibration being transmitted to the vehicle, not vibration within the engine. Controlling loose bolts is normally by the use of a thread sealant like Loctite. Usually not needed in all locations be some of the more critical ones. KDP is an issue that must be controlled either by installing a small tab covering that hose or using a punch to expand the metal around that hole. Later housings had holes that were smaller at the front thus preventing the pin to slip out. Most standard B series and early 24 valves had the pin issue.

 

On my power steering pump there are 2 bolts on either side facing the front of the engine. The brackets shown would bolt up to the inside bolt? My pump has a stud on the outside so I made my bracket to utilize it. Wondering if my pump hasn’t been apart and the bolts switched.