Replacing the front crankshaft seal on a Cummins B series engine
(6BT in the case of the DAF T244)
This guide is a how-to, aimed primarily at DAF T244 owners but will apply to any Cummins B series engine.
Parts, Equipment and Tools
Parts required
- Replacement crankshaft seal kit (part number 3802820, if it comes with a wear-sleeve you must use it or it will leak oil despite what the Dodge forums say! The seals are oversized and the wear-sleeves can be removed in the future without damage)
- Cummins B series timing cover gasket (6B, 6BT, 6BTA, 4B, 4BT, 4BTA). Make sure you have the right gasket for your variant. Euro 1 and Euro 2 variants are different, a DAF T244 needs a Euro 1.
- OPTIONAL Replacement drive belt (part number DAF CBU1716) [8 ribs, 1460mm length for reference]
- OPTIONAL Coat hanger wire or KDP washer if fixing the Killer-dowel-pin.
- RTV Silicone (I used Permatex Ultra Black)
- Loctite (preferably oil resistant variant like 2701)
- Aerosol brake cleaner
- Bar with a 3/8" square drive
- 13mm socket and spanner
- Some cardboard roughly the same size as the fan (50cm x 50cm)
- Torque wrench (capable of 24Nm)
- Hammer (normal ball pein one, not a heavy one)
- TBC
Steps Summary
This is a summary of all the steps involved. Detailed steps with pictures/gifs/videos are included below.
- Tilt and secure the cab. Turn the power isolator to "off".
- Remove lower 4 fan bolts & gently place fan in shroud using cardboard to protect radiator fins.
- Use a 3/4" square to lift belt tensioner and remove auxiliary belt.
- Remove centre bolt and withdraw tensioner and pulley
- Remove damper pulley and withdraw damper.
- Release accelerator spring from front cover.
- Release electrical harness clips (RHD only)
- Undo timing cover bolts and remove cover.
- OPTIONAL KDP fix can be done at this point (see KDP page)
- Remove old crankshaft oil seal.
- Clean gasket faces, seal housing, and crankshaft.
- Using a small amount of RTV smeared on the gasket, faces, replace timing cover but do not tighten bolts.
- Using the metal installer, centre the timing cover on the crankshaft.
- Tighten timing cover screws to 24Nm and remove metal installer.
- Put wear-sleeve in boiling water for 2 minutes, then dry and push onto crank by hand (won't get it all the way).
- Refit the damper and tighten the bolts evenly to push the wear-sleeve onto the crank.
- Clean the crank and wear-sleeve with brake cleaner (no oil whatsoever should be left).
- Put threadlocker (Loctite) on outside edge of seal.
- Using the plastic sleeve inside the seal, slide the seal onto the crankshaft.
- Leaving the seal in place, remove the plastic sleeve and keep for the future.
- Use the metal installer to set the seal to the correct depth by tapping with a hammer.
- Remove the metal installer and slide rubber dust seal (if included) onto the crank.
- Follow steps 1-7 in reverse to refit the engine.
- Let the RTV cure (usually 24 hours)
Detailed Steps (TBC on 23rd July 2018)
1. Tilt and secure the cab. Turn the power isolator to "off".
If you can (the vehicle will start etc), turn the wheels full lock left to allow you easier access into the left wheel well. It can be done without but makes life easier.
Using a bar (I use the handle of a 600mm breaker bar) undo the cab lock. Then switch the jack to "up" and start pumping. Once it's pretty high, put the safety support in place and jack up just until it engages.
Using a bar (I use the handle of a 600mm breaker bar) undo the cab lock. Then switch the jack to "up" and start pumping. Once it's pretty high, put the safety support in place and jack up just until it engages.
2. Remove fan bolts & gently place fan in shroud using cardboard to protect radiator fins.
Cut out a 50cm square piece of thick cardboard. This is to protect the delicate radiator fins from damage when the fan is loose in the cowling. It's not possible to remove the fan cowlings without removing either the lower radiator hose, or the gear linkage at the top, neither of which is necessary.
Take the bottom two bolts of entirely and loosen the top two. There is no need to touch the ones joining the two halves of the radiator cowling. All bolts are 13mm, a spanner (as opposed too a socket) is necessary for the upper bolts.
Remove the 4 fan bolts (16mm socket). They shouldn't be that tight but if the engine turns over put the truck in gear to lock it. Don't forget to take it out of gear before lowering the cab.
I suspended the fan using some long cable ties (3x 30cm ones). The fan is quite heavy and the blades can wedge themselves into the cowling and radiator. To be safe, suspend the fan, this will help later when you need to access the crank and it gets in the way.
Take the bottom two bolts of entirely and loosen the top two. There is no need to touch the ones joining the two halves of the radiator cowling. All bolts are 13mm, a spanner (as opposed too a socket) is necessary for the upper bolts.
Remove the 4 fan bolts (16mm socket). They shouldn't be that tight but if the engine turns over put the truck in gear to lock it. Don't forget to take it out of gear before lowering the cab.
I suspended the fan using some long cable ties (3x 30cm ones). The fan is quite heavy and the blades can wedge themselves into the cowling and radiator. To be safe, suspend the fan, this will help later when you need to access the crank and it gets in the way.
3. Use a 3/8" square to lift belt tensioner and remove auxiliary belt.
Now the fan is off it's possible to take off the auxiliary belt. Use a 3/8" socket in the square and rotate it clockwise looking at the front of the engine. On its return it comes back a long way so be careful not to trap your hand. Be in a good position (I suggest right hand side of the engine) and make sure you have a good grip. A regular ratchet will bring your fingers very close to the idler pulley so be careful. I suggest slackening it, taking the belt off the alternator, then squeeizing the belt through the gap between the tensioner and idler.
Store the belt somewhere safe unless you have a replacement. You could keep the old belt for emergencies if it's intact.
Store the belt somewhere safe unless you have a replacement. You could keep the old belt for emergencies if it's intact.
4. Remove centre bolt and withdraw tensioner and pulley
To remove the damper undo one bolt (size tbc) and take the whole thing off and put it to one side.
5. Remove damper pulley and withdraw damper.
Back down at the damper, use a 15mm socket (careful not to use the 16mm from the fan bolts lest you round them off). These can be tight so use a 6 point not 12 point socket if possible. If the engine turns before you undo them, put the truck in gear to lock it. Remember to take it out of gear before you drop the cab back down or the gear stick will clash with the underside of the cab.
6. Release accelerator spring from front cover.
Unhook the spring on the left side of the engine.
7. Release electrical harness clips (RHD only) and harness
Take the cable out of the clips. You can undo the spaded connectors at the top of the engine. Make sure you take a picture or make a note of which way round they go.
8. Undo timing cover bolts and remove cover.
Use a 10mm socket (and spanner for some of them) to undo all the bolts on the timing cover. It won't hurt to undo them all half a turn first before undoing any completely.
There are 20 bolts, some short and some long so it helps to use a piece of cardboard (perhaps the one the new gasket came with, to keep track of all of them (see my picture).
There are 20 bolts, some short and some long so it helps to use a piece of cardboard (perhaps the one the new gasket came with, to keep track of all of them (see my picture).
9. OPTIONAL KDP fix can be done at this point
10. Remove old crankshaft oil seal.
It's not that easy to get out, especially with threadlocker on it. Put it on a bench and use a hammer and a punch to tap it out from the back.
11. Clean gasket faces, seal housing, and crankshaft.
Scrape off any old silicone with a razor blade. For the inside of the seal, I scraped most off then used a very fine emery paper (1200 grit) to remove the rest. Threadlocker is hard to get off.
12. Using a small amount of RTV smeared on the gasket, faces, replace timing cover but do not tighten bolts.
Put a few bolts in to hold it in place but don't tighten them.
13. Using the metal installer, centre the timing cover on the crankshaft.
Make sure it's held in while you progress to the next step.
14. Tighten timing cover screws to 24Nm and remove metal installer.
15. Put wear-sleeve in boiling water for 2 minutes, then dry and push onto crank by hand (won't get it all the way).
This is not as easy as it sounds but be patient and persistent and try to get it over the lip and on as far as you can.
16. Refit the damper and tighten the bolts evenly to push the wear-sleeve onto the crank.
Doing up the bolts carefully (same number of turns each time) will pus the wear sleeve on straight.