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Chewed up push rod and vexing oil leak

Ducdude

Well Known and Active Forum Website User
VOC Member
Well today was not a good day working on the Shadow...

The goal was to quell an oil leak at the FT exhaust pushrod tube and while
that went as expected as far as getting the seals out and off that was not
the location of the leak. To make matters worse despite warning to take
care and get the pushrod back in the lifter's cup I screwed that up and did
not realize it till I tried to kick it though with the compression release,
I got 2 or three kicks before I realized I messed up..

The damage is one chewed up ball end of the FT exhaust push rod. I pulled
the rod and dropped in an old but serviceable one to evaluate the function
or lack there of. The valve seems to operate correctly and the bike runs
but it does not seem to do so as smoothly or as quietly as before. The
adjustment may be a tad looser then nil as I was quite miffed when I did it,
hence perhaps the reason for the loud valve and ruff running or not.

I will replace the old rod with a new one as soon as I get one but the
question begs to be asked...What other damage do I now have to be concerned
about...What should I look for and how?

To add insult to injury the front cylinder is still leaking on the mag
cover...The head is dry and there is only oil below the head heaviest on the
push rod side on the fins foward of the cylinder and oil drops the mag cover...


So could oil be leaking out between the head and the muff/liner??
Another thought was oil somehow spraying out from the lower pushrod seal?
It's a long shoot but what ever...

The front oil lines and the tappet and valve covers are all sound and dry.
Where else could the oil be coming from? I am open to any Thoughts on this
as well as my new push rod potential damage issues..

Thanks,
Eric
 

passenger0_0

Well Known and Active Forum Website User
VOC Member
Hi Eric. I don't think you would have done any lasting damage through your little misadventure but I can understand your fustration as this is not an easy job. Regarding the oil leak - this can be a problem as the airflows that occur around the engine sometimes blows oil forward. For what its worth, I have had oil leaking from out of the cylinder studs as the rear stud on each of the timing sides is drilled into the crankcase cylinder oil supply line and this region originally only used gasket poo to seal the threads from leaking. These days I blank off this oil supply at the timing cover in all of the engines I do (if the owners agree) and don't seem to have this problem. One suggestion I have read in an old magazine (which I've never tried) is to throughly clean and dry the engine before running the engine stationary and get it real hot. Throw some french chalk at the region of interest which should highlight the source of any leak. Good luck - David
 

timetraveller

Well Known and Active Forum Website User
VOC Member
I agree with passenger0_0. It is most unlikely that anything else will have suffered and if you do not have ready access to french chalk then talcum powder will do but you have to put up with the scent.
 

Ducdude

Well Known and Active Forum Website User
VOC Member
OK more testing with powder has determined that the lower ft exhaust push rod tube seal is at least contributory to the leak at the front of the cylinder....I will dig that baby out and replace it today....The stand in push rod seems to work acceptably with just a bit of exhaust popping on the over run...Still thinking it just needs to be tightened up as it is a clattering / tapping a bit more then normal...

So job one replace the seal job two adjust the valve job three get a new rod in there next week...

Ahhh the difference a day makes....

I got work to do! YEA!!

Cheers,
Eric
 

Ducdude

Well Known and Active Forum Website User
VOC Member
The temp push rod is doing its job and the bike seems to be running
fine-ish...It seems to pull well and idle well and cruse well in 2nd 3rd
most of the time...Then all of a sudden it gets a tad rougher running and
may or may not tend to stall. A bit of time on the carb air mixture screws
seems to have helped? I still think she is running a tad rich as I get
white smoke out the pipe and wet black plugs...

I have 32mm Amal's MK1's running w/o filters and an open pipe with 210
mains...what do you think a good first adjustment would be to lean it out
JUST a TAD? As I said the stand in push rod seems to work acceptably with
just a bit of exhaust popping on the
over run..Which may be the rich mixture or a response to the less then
perfect push rod I am using...Its end being less the perfectly round.

As far as the leak goes more testing with powder had determined that the
lower ft exhaust push rod tube seal was contributory to the leak at the
front of the cylinder. The other 3 sets of push rod seals are also
misting a bit, they are next....I dug the offending seal out and replaced it
and went for a ride...No leak .....

Ahh the difference a day makes....

Cheers,
Eric
 

Howard

Well Known and Active Forum Website User
VOC Member
White Smoke???? Surely black smoke for rich!!! Blue smoke for oil. White smoke signifies something not good, but I can't for the life of me remember what, I seem to remember it being head gasket on a car (water cooled), but that can't be your problem. Are you sure you're not burning oil?

I'm running 32 mm Mk1s on 240 main jets, and may go bigger yet. In my book, exhaust popping is weak, not rich - on the pilot.

Pushrod? As everyone seems to agree, if it's running now, you probably haven't damaged anything seriously. I've done it - made a groove on the ball end - it can be a pig, I never put push rods in at the end of a long day.

H
 
Last edited:

RedRyder

Well Known and Active Forum Website User
VOC Member
Eric,

I agree with Howard that the white smoke suggests oil. And, your description of wet/black on the plugs also suggests too much oil. Your machine may not be equipped with the metering wires and/or might have shot valve guides - my Red Rapide was a low mileage barn find but nevertheless had shot valve guides. Haha, maybe they can "wear" while they rot away in the barn! Anyway, a temporary POSSIBLE fix to that is to run hotter plugs, one or two hotter. And, if you don't have metering wires in there adding them will almost certainly help if things haven't gone too far with the guides.

Bev
 

Alan J

Well Known and Active Forum Website User
VOC Member
I did say the other day it takes 10 years to sort out ones Vincent!!-If the pushrod seals persist in "leaking" it can be a sign of too much crankcase pressure-but that is another story! White smoke? all I ever get with this horrible modern fuel is black soot! it sounds "weak".
 

b'knighted

Well Known and Active Forum Website User
VOC Member
I have found the exhaust popping on overrun can come with any leak in the exhaust system. Mine has a pinhole where the rear pipe joins and does a single pop as the throttle is shut under load. Before I replaced its lace silencer it popped a lot more.
 
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