Had my 318 rebuilt last month. The crank didnt need replacing but I was told that there was some slight corrosion where the rear main seal goes. I was warned that this might result in a very slight oil leak but that this might be compensated for by using a new rubber seal rather than the rope seal that was taken out.
Engine is now back in and running fine but the rear main seal is leaking to a point where it is trying to coat the back axle with oil. Have now done around 400 miles since the rebuild and it is gradually getting worse. Am I right in thinking that the only way to cure this properly is to fit a rope seal?
The rope seal that was in it before, was there for 30 years and didnt give me any problems.
Would be really grateful for any thoughts and if the answer is a rope seal, where can I get one from?
Thanks Guys
they should have cleaned corriosion up using 1200 wet n dry and some wd40 or diesel.
then a quick polish, leather chord or strap and metal polish or tcut or tooth paste anything slightly abraisive....
clean it all off.
sounds like they were trying to swerve responsibility for leak.
[Apologies if this was a mate who rebuilt for you ]
i'd be asking them to do it again.... and to explain their choice.
did they align bore the case....? if so seal housing will not be concentric with crank anymore, or may not have been anyway.... might dictate rope seal from now on, Rope is more forgiving.
Or the rubber one will need to be shimmed one way or the other.
new build should be leak free...
If the crank has a nice knurl to the area that the seal runs on
a rope seal is the way to go.
a nice deep knurl on crank+ ribbed face of a rubber seal do not live happily togther, just wear away.
if the knurl has worn off the crank then the rubber seal is the way to go. it has a ribbed face a reverse version of the knurl to the crank
that does the same job of drving oil back into the sump.
if you find no knurl and a leaking rubber seal
cut 2 lengths of thin shim (metal sheet) to line the seal housing with to act as a packing, and glue the next rubber seal in over thais packing strip with silcone sealant or as noted shim one side or the other to cater for an align bore.
fit rubber seal dry first, with no crank, and check that the ends of the lip do not pucker up when the housing is bolted down
aim to fit it so it is offset from the parting line of the cap by 1/8/-1/4 of an inch i.e offset it so if it leaks at the join it doesn't just spread through the cap parting line with the case.
this is the cheapest by volume, you can pay for loktitie or yama bond if you want turns into a very very very thin gasket.
glue the ends of the seal with it or slicone or super glue.
Rope seals
used to be fibreglass and asbestos mixed with some kinda natural rope fibre, worked very well
these days god knows what, but they are not as good
3 choices
buy
1) a rope seal for your motor
2) a vintage asbestos seal for a ferguson tractor off ebay
3) buy a nice length of gland packing from this geezer https://www.ebay.co.uk/itm/182855133895 ... 0160100508
i think the 12 mm stuff might be the go..... having purchased an expensive ropse seal from www.bestgasket.com and discovred that it was just a length of gland packing, my view of best gasket changed considerably. if you buy 50 cm you can have a few goes at getting it right
i worked out that the crankshaft speed at 6000 rpm doesn't breach the specification for this packing
if you can find one of the holden seals used in the video, it can be used on a mopar hemi 6 and therfore i think it will fit a mopar 318 as well due to same 2.5 inch journal and seal size basiclaly the seal is quite long or try ACL HN065 the slant 6 version
they have a good rep but were made by ACL who like many aussie motor trade suppliers went backrupt as holden ford et al pulled out of Oz
Dave
The Greater Knapweed near the Mugwort by the Buckthorn tree is dying
both types of seal can be stuffed in with the crank in place but lowerd on the main caps
rope involves a lasoo made from wire to pull it through and a long pice of seal to start with
rubber invokves feeding it round
both should be oily as hell to assist with getting it in and first start-up.
can't imagine success with either method.
miserable messy job
better off out
Dave
The Greater Knapweed near the Mugwort by the Buckthorn tree is dying
Thanks for all the info Dave. Certainly given me something to think about.
Would love to hear from anyone else out there who has had problems with newly fitted rear seals in a stock LA 318.
I don't want to go out and buy a VW T4 but I might be forced to if I cant fix this within the next 4 weeks (Ferry booked for June!)
i ran around for years rust proofing the road and underside of my car
not smart or clever but needs must .. its a hemi 6 notorious for this problem.
bottle of oil in the boot and check the oil level each week.
a small amount whipped about by the air under the car goes a very very long way... even up the rear panels at the tail end......
if you are getting a ferry they might appreciate the rust proofing
other option is to take off the cap and put a groove across the cap bearing at a 45* angle
check which way the crank turns and put the groove in the direction that drives the oil out to the front of the housing
i.e bias the majority of the oil splash from the sdie of the mian beraing forwards instead of 50:50 front and rear.
example here
this is a RB beraing from mancini presume RBs spin the same way they fit the same trsnamissions so they should
no idea why they have 2 groooves i'm sure 1 would work..
you'd need a dremel, they say special groove in the blerb can't see whats so special. i think you could make one
