Need help id'ing the Missing Bolt that is causing an oil leak

[jim515]

I have an oil leak starting from the left side of the lower engine above the starter. Looks like a bolt is missing, possibly causing the gasket to leak. I don't know what the bolt is, type, size length. I couldn't figure it out going through the service manual. So I am seeking help.

Last Oct I went and got new tires, when the service writer was looking over the bike he pointed out I had a bit of oil on the lower part of the engine and asked if I wanted them to look at it. I said no, as I typically do work on my bike over the winter. Fast forward several very cold months later I checked over the bike today for a ride tomorrow starting with air pressure. Then found that the lower part of the engine including the entire oil sump pan is covered in oil and dust mixture. I traced it to this picture, while noting the oil level is higher than I fill it... and looks milky. I haven't drained that yet. I am honestly worried about what I would find.
During this I noted the overfill for the radiator fluid is a dry....  making me work some more.....

After removing the body work, I located what I suspect is the culprit 



The oil is seeping from above the circle for the missing bolt. Going down and back. The starter has a layer. The front of the oil pan has a good amount. None above it. None seeming to come from elsewhere. Which is why I believe this is the source.

What is the bolt type? What is that connected to? Is the part labelled "Clutch?" correct?

All help and advice is welcome.

[Coconut]

Hi,

I believe that Bolt is Triumph Part Number T3202303 - M6 x 28mm.
Item #7 here : Hermys Triumph eStore
You could try taking out the adjacent bolt and carefully trying it.

Sorry to be the nearer of bad news, but I am concerned that your report of "Milky" coloured engine oil,
low coolant level, and higher engine oil level, is a result of the coolant mixing with the engine oil.

Milky engine oil is a classic sign that water has been mixed with engine oil
and one of the most common causes is a leaking cylinder head gasket,
although there could also be other reasons.

My advice would be NOT to run the engine, as this could cause damage
due to the reduced lubrication of contaminated oil, and potentially higher pressure
due to the extra volume of fluid, which could also affect other seals.

The contaminated oil will need to be drained, and flushed out, as will the Coolant,
and the cause of the cross contamination identified and fixed.

You Dealer will be best placed to do this - but have your wallet ready - it's likely to be expensive. 

The area labelled as "Clutch" in your Photo houses the Starter Flywheel and the Starter Sprag Clutch.
( The main engine/gearbox clutch is on the other side of the engine )



Cheers 

[jim515]

Hey Coconut,
Good to hear from you.
The oil color is what I fear. I will drain it today and get a good look at it. It could just be from my putting in a bit too much in the last change. It is about 1mm to 1.5mm higher than the top line. I am being cautions about this as I know it is NEVER good when any fluid mix.

Finger crossed, I am just not seeing the color of the oil well through the sight glass.

(My older brother is a certified master mechanic and owned a bike / quad store for years. So when he talks about this stuff I listen to pick up info.)

I will use my calipers to confirm the length and I am sure I have a M6 bolt that I can use to check the threads.

Question do you think Lock Tite or similar substance should be used on the bolt? Seems like a weird one to have backed its way out. I would suspect it has a pretty high torque spec.

I will update on what I find about the oil when I drain it this morning.

-Jim

[Coconut]

Hi again,

The tightening sequence is explained in the Service Manual when the Crankcase upper and lower halves
have been separated.  The M8 bots are tightened first in a specific order, followed by the M6 bolts.

I believe "your" bolt is number 16 in the following Image, and as you can see it is only tightened to 12Nm.
Although you won't need to worry about the tightening sequence, don't over tighten it !
While you're there check the others too, including the M8 Bolts that should be tightened to 14Nm.

There's no Gasket used between the two halves - a thin bead of Silicon based sealer is used.
( At the factory "Threebond 1215" is used ), so nipping up a bolt where there is a leak
may or may not seal it - depending on how bad the leak is, and the integrity of the sealant in that area.

Viewed from underneath :



Hopefully as you say, it's just a slight weep from that area due to the bolt having worked its way out.
a number of Members have reported over the years that these bolts seem not to have been tightened
straight from the Factory !

It may be that the oil just looks "milky" through the sight glass, but not when you drain it,
and the Coolant just needs topping off with the correct pre-mixed type. 

Cheers 



 

[jim515]

I looked at that diagram yesterday and wasn't sure if the bolt was there. Thank you.

If you look at the picture, the bolt to the right you can see a bit of the sealant. I was not sure if that is used in addition to a gasket. If the gap was enough the sealant might be a bit thin at that spot now. The "field expedited" fix would be to put sealent on the outside to hold it in. I doubt that is a long term solution. Yet dropping the bottom of the engine, cleaning and resealing  wouldn't appear to be either a simple or cheap task.

My sense of humor thinks, Step 1, Invert the engine.  "Hey that violates the rule, keep the rubber side down!"

-Jim

[jim515]

Hey Coconut,

The bolt seems to be number 19. I found a bolt at the store that fits, though I might buy a new one that is a perfect match.

I checked the bolts with the torque wrench and found quite a few were loose. Like, 17, 16, 12, 7, 8, & 9. I also checked all the oil sump bolts, also 12 nm and found a bunch of those were also loose taking usually 1/8th a turn to meet the spec.

Good news, the oil sight was quite dirty and the lighting not good. The oil looks fine, like it had about 1200 miles on it, and smells just fine. Phew.

The overflow on the radiator being quite low is just probably natural evaporation. Colorado is a semi arid climate.

 

[digital]

If I remember correctly, the place of that missing screw is exactly where the plastic cover that covers the starter motor is attached.

[jim515]

Digital,

What plastic cover for the starter? I just looked that up and I see there is a cover. The screws to hold that in place are pan head M6 x 16 per this https://www.triumphestore.com/a/Triumph_2013_Trophy-1215-SE/_51513_7054289/Starter--Alternator/100061497-1-2.html.

Bolts 11 and 12 are the right size, not the right placement for the missing screw.

What the heck did I do with a cover?

-Jim