Britbike forum

Classic British SparesKlempf British PartsBaxter CycleBritBike Sponsor SteadfastCyclesThe Bonneville ShopLowbrow CustomsGirling Classic MotorcycleLucas Classic MotorcycleHepolite PistonsIndustrial tec supply Classic Bike Parts Cheshire

Upgrade Your membership! Premium Membership Gold Membership Vendor Membership

New Sponsor post
New FAQ post
Photos on private message
by Mal Marsden - 06/16/22 7:00 pm
Manuals on DVD - Buy 4 for 3
All 4 DVD Manual
Member Spotlight
ricochetrider
ricochetrider
Pennsyltuckey
Posts: 11,651
Joined: May 2007
ShoutChat
Comment Guidelines: Do post respectful and insightful comments. Don't flame, hate, spam.
Top Posters(30 Days)
reverb 87
Allan G 56
kevin 50
Top Likes Received (30 Days)
Cyborg 33
Newest Members
Jim Harris, Cuppy, budpotter, Mark Sharp, Ian Scotland UK
12,160 Registered Users
Who's Online Now
5 members (Rusty Goose, hardarser, Magnetoman, MrMarty51, HughdeMann), 24 guests, and 15 robots.
Key: Admin, Global Mod, Mod
Forum Statistics
Forums35
Topics76,311
Posts772,635
Members12,160
Most Online151
May 8th, 2022
Previous Thread
Next Thread
Print Thread
Joined: Dec 2013
Posts: 13
M
Britbike forum member
OP Offline
Britbike forum member
M
Joined: Dec 2013
Posts: 13
After a nearly 2 year hiatus, I am back in the shed fettling the 1966 T100. Yesterday I started her up for the first time. Started without too much drama and settled into a steady tick over.

A quick check around the engine for oil leaks immediately indicated oil pouring out of the points cover. All I could think was that I'd fitted the (new) oil seal the wrong way round. Further investigation showed that the hole in the timing cover casting which allows the leads from the points/ ignition trigger to exit the engine goes directly into the timing chest, with a 90 deg passageway for the cables.

This hole goes directly to the timing chest

[Linked Image from i.imgur.com]

There is a hole at 90 deg to allow the cables to exit

[Linked Image from i.imgur.com]

How is the hole to the timing chest normally blocked? Nothing is shown in the parts list. Silicone plug?

Thanks in advance
Peter

Triumphs on eBay
Joined: Apr 2017
Posts: 871
Likes: 2
M
Britbike forum member
Offline
Britbike forum member
M
Joined: Apr 2017
Posts: 871
Likes: 2
On my 67 tr6c it rubber plug that wires go through.

Joined: Apr 2017
Posts: 871
Likes: 2
M
Britbike forum member
Offline
Britbike forum member
M
Joined: Apr 2017
Posts: 871
Likes: 2
[Linked Image from i.postimg.cc]
No. 13 if it helps

Joined: Nov 2008
Posts: 3,641
Likes: 57
D
Britbike forum member
Offline
Britbike forum member
D
Joined: Nov 2008
Posts: 3,641
Likes: 57
The rubber plug is more to keep water and dirt out. There should be no oil behind the points cover.


1968 T120R
1972 T120RV
Any advice given is without a warranty expressed or implied.
Joined: Mar 2019
Posts: 56
Likes: 5
S
Britbike forum member
Offline
Britbike forum member
S
Joined: Mar 2019
Posts: 56
Likes: 5
I recently had to have the timing cover off my T100T. The 500 engine is not provided with a gasket between the crankcase and the timing cover, unlike the 650s. Did you put adequate sealer around the entire edge of the cover casting? It should not leak through the joint between these two holes unless the faces are not flat for some reason.

One reason for leaks around this cover can be if you have changed from the original Philips screws to cap head (Allen screw) alternatives; some of these in screw kits can be too long and bottom out in the tapped crankcase hole before clamping the cover down properly (ask me how I know!)


Current bike: 1969 Daytona
Previous bikes: '59 Tiger Cub, '62 Bonnie, '67 Bonnie, '69 Bonnie, '70 BSA Lightning, '71 OIF Bonnie, '73 Honda 500-4
Joined: Oct 2003
Posts: 4,367
Likes: 27
D
Britbike forum member
Offline
Britbike forum member
D
Joined: Oct 2003
Posts: 4,367
Likes: 27
On my 650 a seal marked PW worked much better in the points cavity like they do as crankcase seals.

Do you mean that when the cover is on the 500cc engine there is a clear hole straight into the timing chest that oil can just pour out of rather than just a hole for the wires?I don't recognise the hole in the edge of the cover adjacent to the screw hole unless I am not interpreting the second picture correctly. I had a look at a pic of another cover and it didn't seem to have that hole.



Dave

Last edited by dave jones; 10/01/19 3:47 pm.
Joined: Feb 2014
Posts: 1,514
Likes: 51
Parts Dealer
Offline
Parts Dealer
Joined: Feb 2014
Posts: 1,514
Likes: 51
As others have stated, oil should not be getting passed the oil seal

I like to use Yamabond or a good silicone and plug the points lead hole to prevent debris from getting into the points cavity

EMGO seals, USA seals are all good when used to seal up the points cavity

Joined: Dec 2013
Posts: 13
M
Britbike forum member
OP Offline
Britbike forum member
M
Joined: Dec 2013
Posts: 13
As Dave Jones says, there is a hole straight into the timing chest. Oil seal is fine. These photos should make it clearer :

looking from inside points cover, daylight can be seen where the timing chest would be. Ignition wire can be seen exiting points cover through the normal 90 deg hole.
[Linked Image from i.imgur.com]

looking from back of timing cover, note daylight, so oil can flow from timing chest into points
[Linked Image from i.imgur.com]

Note trace of silicone showing that the hole is only partially covered by the timing chest casting, allowing oil to flow out.
[Linked Image from i.imgur.com]

This can not be standard, can it................?

Joined: Sep 2013
Posts: 3,748
Likes: 251
Q
Britbike forum member
Online Happy
Britbike forum member
Q
Joined: Sep 2013
Posts: 3,748
Likes: 251
the wire path may be a bit different for different years ?
ive only seen where the points wire hole goes into the timing side and the timing side has it own wire exit hole
(where the 2 greasy wires exit )
[Linked Image from i.ebayimg.com]
...so no 90deg bend .


Last edited by quinten; 10/02/19 4:04 am.
Joined: Nov 2012
Posts: 2,436
Likes: 136
K
Britbike forum member
Offline
Britbike forum member
K
Joined: Nov 2012
Posts: 2,436
Likes: 136
Hi Macchi,

I have no first hand experience of the unit 500, but I really don't think a direct route from the timing chest to outside would be original.
There is masses of oil splash in the timing chest, and that hole is in the ideal place to collect oil above the bolt boss, and aided by the crankcase pressure fluctuations, push it the short distance to what is effectively acting as a drain hole to the outside.

From your pics, I would guess that the hole for the wires was originally much smaller diameter (maybe 1/8 to 3/16 inch?) at say 45 deg, such that it didn't break into the timing chest at all.

For whatever reason, it looks like a large hole as been bored from the inner surface of the cover. The hole looks a bit rough and also goes very close to the outside surface. It doesn't look original.

That hole needs plugging in some way. How you go about it will depend on your facilities to some extent. I offer a "simple" method which I think will work, but if it still weeps it won't stop you trying more engineered ideas.

Thoroughly de-oil the area with solvents, rough-up internally with small rotary wire brush, de-oil again. I would then thoroughly heat the passageways with a hot air gun or similar.
Clamp the cover down to a flat plate that covers the 3 nearest bolt holes, with a bit of rubber sheet betwwen the plate and cover. Plug the "drain hole".
Slowly fill the cavity by running some epoxy (Araldite or whatever) down the side of the hole into it (to mimimize trapped air bubbles). You can fill all the way to the points cavity, or just half way. I feel all the way will give max security.
Give it plenty of time to fully harden. You can then drill the necessary hole to the minimum size for the 2 wires with sleeving (much smaller than what exists at present) at the appropriate angle to avoid breaking through to the timing chest.

Best of luck! Let us know how it goes.

Joined: Jan 2014
Posts: 3,983
Likes: 48
R
Britbike forum member
Offline
Britbike forum member
R
Joined: Jan 2014
Posts: 3,983
Likes: 48
...a friend had a 64 5TA and does not has that big hole; so better to weld there; is easy and then pass an smaller drill and just that. Take a look at other cover in the internet or measure the wires.

Joined: Jan 2017
Posts: 2,167
Likes: 151
T
Britbike forum member
Offline
Britbike forum member
T
Joined: Jan 2017
Posts: 2,167
Likes: 151
Hi Macchi Man, Are you sure you have correct motor case? Looks like you have distributor type motor, that uses the earlier smooth timing cover E3693 without points. Looks like 1963 was last year for this case casting & cover.

The 1966 500 parts book shows E4360 timing cover which you have. However the corresponding motor case is cast differently with metal where your leak is on case & passage is drilled to pass wires through the motor case starting in 1964. Quentin's photo shows case that goes with the '66 cover & motor. That's what a '66 motor should look like.

'66 T100 case should look like this eBay photo. You can see the passage for wires above screw hole & how the casting itself was modified to accommodate this passage.

https://www.ebay.com/itm/Engine-Motor-Crankcase-Case-Half-Triumph-500-T100-T1114/133182147001?hash=item1f024649b9:g:xY0AAOSwvnddLkpv

A fix would be to plug the back side of the wire hole & route wire out front as you did. An alloy rod ground to fit & loctited in with sleeve/bearing mount, then filed flush & back side of cover flattened on some emery paper should provide leak free fit. Looks like the sealant you used should seal good then.

Be sure to seal points wire to keep water out of points case. I wonder if the original rubber grommet 70-4707 could be cut shorter & siliconed in? Even riding in fog can cause misfire from moisture if wire is not sealed well, not to mention rain or puddles.
Don


1973 Tiger 750
Joined: Dec 2013
Posts: 13
M
Britbike forum member
OP Offline
Britbike forum member
M
Joined: Dec 2013
Posts: 13
Wow! The power of the Forum. It's now clear that I have a mismatch of parts.

Thanks so much to everyone for their input. I'll see which is the best method for me to block off the hole and continue on the journey.

Great!

Peter

Joined: Sep 2013
Posts: 3,748
Likes: 251
Q
Britbike forum member
Online Happy
Britbike forum member
Q
Joined: Sep 2013
Posts: 3,748
Likes: 251
Originally Posted by TR7RVMan
Hi Macchi Man, Are you sure you have correct motor case? Looks like you have distributor type motor, that uses the earlier smooth timing cover E3693 without points. Looks like 1963 was last year for this case casting & cover.

The 1966 500 parts book shows E4360 timing cover which you have. However the corresponding motor case is cast differently with metal where your leak is on case & passage is drilled to pass wires through the motor case starting in 1964.


i think you nailed it Don [Linked Image from i.ebayimg.com]

the older style distributor case-half (above) would not need/have the cast in " wiring through hole "

as seen above middle-front cover screw hole [Linked Image from i.ebayimg.com]

--some extra spooges on sealant would probably work to seal the mix of parts --
but Don's idea of a permanent aluminum half plug would be better
wouldnt be hard to do , even with the simplest of tools .

Joined: Dec 2013
Posts: 13
M
Britbike forum member
OP Offline
Britbike forum member
M
Joined: Dec 2013
Posts: 13
Spot on. I have the distributor type case (half). The primary drive side case has the engine number T100SS/H432** Looks like I have a bitsa!

An aluminium plug has been machined and will be fitted.

[Linked Image from i.imgur.com]

Joined: Sep 2001
Posts: 3,498
Likes: 43
G
Britbike forum member
Offline
Britbike forum member
G
Joined: Sep 2001
Posts: 3,498
Likes: 43
There are three types of timing covers, early distributor type, early points running on ex camshaft but still with bushing type crank and finally the type with points running off camshaft but with new holes and oil seal for the end fed crankshaft.

With the early case half you must be using the second type to allow you to feed the oil to the bushing crank while having the points running off the camshaft. The real problem is that your case half does not have the extra metal to seal the points area while allowing for a tunnel for the wires. The hole in your cover looks to be about the same size as the ones I have but the added mod is the 90 degree turn as you have pointed out. The solution is is to weld up the back of the hole to solve the oil leaking out then just seal the wire hole (once the wires are pulled through) to keep the road crap out.

Quinten's second photo above shows the extra metal for the wire tunnel

Gordo

Late cover showing hole for wires, similar in size to yours

Click to enlarge
[Linked Image from i.postimg.cc]

Hole in later case for wire to come out

Click to enlarge
[Linked Image from i.postimg.cc]

Close up of case difference to show wire tunnel

click to enlarge
[Linked Image from i.postimg.cc]


The roadside repairs make for the best post ride stories.

Moderated by  John Healy 

Link Copied to Clipboard
British Cycle SupplyMorries PlaceKlempf British PartsBSA Unit SinglesPodtronicVintage MagazineBritBike SponsorBritish Tools & FastenersBritBike Sponsor






© 1996-2022 britbike.com
Powered by UBB.threads™ PHP Forum Software 7.7.5