Modify TST KDP Tab for 93

[Dave M]

I been searching for posts on using TST tab kit for my friends 93 and most of the 1st gen links were broken. I understand the tab might need modified due to a step up either on the closest bolt or on the dowel hole. I'm trying to get an idea what to do ahead of time. What is the best way to modify the tab? Would grinding it to fit work? I just did my 97 with the TST tab kit it and it worked good. Also tightened up case bolts and red loctited them.



Also sounds like the front cover gasket is also different but the front seal kit seems to be the same. How can I be sure to get right one?



I'm going to replace water pump, radiator hoses and serpentine belt and remove radiator and replace coolant. Any other tips suggestions are appreciated. I plan on using the gray sealant on both sides of front cover gasket, since that worked for me. Also how can I tell if the 93 has an intercooler. Is that the radiator looking thingy that my turbocharger is connected to. I'm new at diesel stuff but learning.



Thanks, Dave

 

[Bob Beauchaine]

While you are in there there are a total of 5 bolts, 1 of which is the bolt holding the "tab", that hold the front cover to the block. They are all 10mm and have been known to come loose and do as much damage as the dowel pin. You can remove 4 of them, clean and loktite them. The 5th is behind the Vacuum/PS drive gear, you can loosen, clean and re-tighten it but you'll have to bend a 10mm open end wrench to do it. BTW I saw a cam broken in 3 places by 1 of these bolts. #@$%! I did the same things you did and it took me about 6 hrs total.



Good Luck!

Bob

 

[Dave M]

Thanks for info Bob. I did loctite the bolts you mentioned but never found the hidden one. I'll look behind the vacumn pump gear. I just tightened the other bolts like cam etc. I'm still curious how you guys that have used the TST tab have made it work. Some have said they bend it but sounds like grinding should work too. I'm expecting the fan assembly and rest of stuff to be same as my 97. Any more ideas let me know.



Thanks, Dave

 

[AlK]

The first gen trucks 91. 5 - 93 have the intercooler. Yes, it is next to the radiator.

 

[Dave M]

Thanks "ALK". Just now I had my friend trace the hose from turbo to radiator and he confirmed it that it's going into the intercooler next to radiator. Thanks for confirming that for me.



Dave

 

[AlK]

Dave, for your info.

On the first gen trucks (non-intercooled) the piping goes over the top of the engine and goes directly into the intake horn on the drivers side.

---

Al

 

[Dave M]

ALK

I was wondering how they ran the lines. Makes sense to route that way. Them hoses are big so they must clutter up the top of engine.



Thaks for info.



Dave

 

[Ncostello]

Let me look on my photo CD at work tomorrow. I may have the photo which shows the dowel bore with the bossed or raised area around it. You'll then understand why a flat tab wont work. It can be modified by bending the tab... or making a new one. I'm pretty sure I have a photo that'll work.



Driving the dowel pin home... then staking the inner bore with the proper punch will produce a dimple that will not allow the pin to come out. The pin is a fairly snug fit in the bore. Any dimple whatsoever will prevent it from wiggling out. Add green LocTite to a de-greased bore and its not going anywhere.



Cummins serial number can reveal the right gasket. Also the Cummins Grey RTV triple bond stuff is great. Its much better than ordinary Grey RTV. I used it on both sides of my gasket. Seals up tighter than a drum.

 

[Dave M]

NCOSTELLO:



Thanks for the reply. It would be great to see a pic of the bore ahead of time to see what I need to do. I ordered the TST tab and don't have tools to make one so I will either bend it in vise or grind it with bench grinder... just have crude tools.



Good idea to stake the hole, even though I'm using a tab, so I need to buy a punch that will work and I have green loctite for the pin and red loctite for the inside case bolts. I will clean good with brake cleaner ahead of that and maybe alcohol and compressed air.



I don't have the cummins serial number but I figure it's on the engine plate so I'll get it before ordering the cover gasket from Dodge. Is the grey RTV that comes with the TST kit good as the Cummins RTV? I used that on my 97 and it seemed to work.



I'm not a great mechanic but I figure I can do a better job than Cummins (and so does my friend) since I have access to all you TDR guys with great knowledge to share and I know the bolts inside need taken care of too. He was amazed at all the knowledge I had of this project and would rather I do it for him than Cummins, thanks to all your great posts on this subject.



Thanks all. Any other ideas or comments are appreciated. I got about 1 1/2 weeks before the job. Don't want to screw up someone else's truck... but I'm doing it for free.



Dave

 

[Ncostello]

In the photo you can see the bolt head that the tab must be secured by. You can also see that the pin bore is on a different level than the bolt head. Thus a flat metal tab can't be bolted up under the bolt head and run flat across to cover the hole. It would need bent in a stair step fashion. On some trucks it is flat across there. Not all timing cases are the same. This particular case is a 24V with the improved design... or a ring ridge around the pin bore diameter. You can sort of see it around the bore opening. Also... I"m sure the Grey RTV with the kit will be fine.

 

[Ncostello]

Oh... I'm also not sure if you wanna use red loctite on anything. Blue will hold it. Red usually requires heat to remove it... if it comes loose at all. You may have to tear the engine down someday!! At least thats my experience with Loctite Red.

 

[tugboatphil]

I'm no engineer, and only a fair mechanic. I've also asked numerous stupid questions before, so here goes... .



If the tab is held over the dowel hole, and the bolt is loctited, why does the tab need to be flush across the hole? Even if the dowel backed out after being punched in and loctited, it couldn't push past the tab. And if the tab bolt backed out enough to let the dowel pin out, wouldn't you be in just as much trouble with the tab bolt about to fall out??



I stand ready to receive slings and arrows!!



Oh yeah, I'm also speaking as one who still hasn't done anything about his own KDP.

 

[Ncostello]

Well... all I can think of is that there is no way of installing the tab without putting at least one bend in it. Otherwise you'll be bending the tab with the bolt as you tighten down... which puts the bolt in a bind. The second bend of the stair step would not be needed perhaps but would definately look nice flush against the pin bore opening.



The difference in elevations of the bolt head surface and the pin bore opening surface is like 1/4". So as you tighten the tab down its going to conform to the difference in elevation no matter what. I don't know how thick the tab is... but I'd rather do the bending on my bench.

 

[Dave M]

NCOSTELLO: Thanks for the great pic of stepped dowel hole. You said that was a 24V. Is the 1st the same or similiar to that pic? Is see where it is kinda hard to tab that hole with the flat TST tab. I will definitely want to gouge the hole with a punch for insurance and do what I can to bend the TST tab. The dowel hole and bolt hole were flat across on my 97, so the tab fit flush against the case.



Hmmm... Red loctite verses Green... I used red loctite on my 97. . oops... cause most of the threads said to and the TST tab kit came with it to use on the longer bolt that was included with it. The tab looks like about 1/4 inch thick... pretty hefty looking. Looks kinda hard to bend in vise. Worries me that bending on the tab might result in the tab bolt not being tight as TUBBOATPHIL indicated on his reply. I don't want that bolt falling out. Sounds like someone needs to sell a tab for this application.



Siounds like it won't be easy to bend to fit. Two bends would look good I agree. maybe grinding a little on the tab near the hole would help with that bend. Anyone have a tab for sell that would fit better? I've got a week from friday before I start the job.



Thanks all for great replys. Keep em coming.



Dave

 

[Greenleaf]

I made a stepped tab cause it isn't a tough job and cause it had to be done. I used a piece of mild steel. It wasn't very heavy but there is no way I could bend it with my bare hands. The hole I drilled was just a hair bigger than the bolt. Then I got fancy with bending the tab by using heat and pliers.



I made a stair step in the tab. Also I had to grind around the bolt hole as there isn't much room to have extra material hanging out from under the bolt head.



This worked out real slick like. I had thought of making several but it was so easy, nobody out there would have paid money for one





-S

 

[Dave M]

GREENLEAF:



Hmm... Sounds easy to make but since I already ordered the dang TST tab I'll first try modifying it with a step like you did. Guess I'll have to wait til I get er apart afore I tackle the tab.



Dave

 

[JLEONARD]

Tugger I believe you are correct. I also would only stake (punch) the pin in place. I wouldn't even loctite it.

We stake safety critical connections every day here so it's second nature to me.

But I won't slight anyone who wants to do all that tab work either... . more than one way to skin this one.

Jay

 

[Ncostello]

Not sure if the 1st gen cases are similar... but probably. Cummins didn't make but 3 or so of these cases. There were very little differences in them. So the 24V case could be very similar except the one shown is the "improved" hole design and drilled for a VP44 pump.



If it were me making a tab I'd just use 16th inch mild steel. I've seen guys use a section of hack saw blade. Thickness doesn't really matter. Thin will work. Just don't use brittle steel as it can vibrate and eventually crack. Use a mild steel like A36... which is basically plain steel.



16th inch will bend very easily and won't take up much thread on its holding bolt. 1/4" is just plain overkill and you'd have to get a longer bolt for sure.

 

[Paychk]

Here is a shot of a 92 housing and the tab I fab'ed for mine.



https://www.turbodieselregister.com/forums/showthread.php?p=1032296#post1032296

https://www.turbodieselregister.com/forums/attachment.php?attachmentid=47985&stc=1

 

[tugboatphil]

I was thinking the elevation difference was reversed. That the tab bolt hole was higher than the dowel hole. If the dowel hole is higher, then I could see where you might not get it seated properly, causing aproblem later on.