Ds starter motor bolt!

Honda motorcycles often use M7 bolts, studs and cap screws. The attached image is for a set of M7 barrel studs for GY6 Honda and Honda clone engines. The long ones are 180mm and the shorter ones 165mm. Time you add a nut to the thread, the under head length is going to be close to 150mm.🤷‍♂️

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Greenpeace said:
Honda motorcycles often use M7 bolts, studs and cap screws. The attached image is for a set of M7 barrel studs for GY6 Honda and Honda clone engines. The long ones are 180mm and the shorter ones 165mm. Time you add a nut to the thread, the under head length is going to be close to 150mm.🤷‍♂️

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I did wonder if it would be possible to just replace our friend's bolt with a stud given its length, but I don't know what it has to clamp and how. A stud would also bring the benefit that you could potentially extract it before removing whatever it is holding down (if it does not have some other secondary function).
 
Sorry for the delayed response.... got carried away on another problem!
Yes, it needs to be 150mm under the head (or longer - I can thread and cut), AND a 7mm shaft.
This bold goes through two lugs on the gearbox, through the starter motor locating ring, then into the starter. I had cut an 8mm rod, welded a nut to one end, THEN discovered it wouldn't go through all the lugs! Bugga!!
This an engine rebuild, started by someone else, then passed on to me.... third one this year!!!
They can't find the original bolts, hence my problem. I can order them from Yurrop, but the post is SO slow.... My usual local metric suppliers are lost on a bolt this length.

S
 
faulksy said:
I read on a French forum ages ago that they were made for Citroen by a local company and it’s actually a pine tree not chevrons.
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That is interesting. I've never heard that one before. It does look like a pine tree, not chevrons!
 
skp said:
Sorry for the delayed response.... got carried away on another problem!
Yes, it needs to be 150mm under the head (or longer - I can thread and cut), AND a 7mm shaft.
This bold goes through two lugs on the gearbox, through the starter motor locating ring, then into the starter. I had cut an 8mm rod, welded a nut to one end, THEN discovered it wouldn't go through all the lugs! Bugga!!
This an engine rebuild, started by someone else, then passed on to me.... third one this year!!!
They can't find the original bolts, hence my problem. I can order them from Yurrop, but the post is SO slow.... My usual local metric suppliers are lost on a bolt this length.

S
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Sounds like a real saga. Why not enlarge the holes to 8mm?
 
Hang on.

So this bolt screws into the starter (long side of the hex in your picture) and THEN feeds the short side through the entire stack of stuff (g'box housing and what else) and is secured with a nut at the other end?

Asking because faulksy's picture above looks like the bolt is fed from the opposite (g'box end) side through everything and clamps the starter and everything else between the spacer (= the hex in your picture) and the end of the thread at the long end of the shank (to be honest, I don't even understand why it needs that spacer or the hex in the middle looking at faulksy's picture).

Either way, should be possible to just enlarge and tap the starter, right? And it doesn't have to be 1.25 pitch if you don't like that, you can have 1mm pitch if it makes things easier.
 
I think you are confusing the 150mm bolt ('1' in the photo) with the other starter securing bolt that Faulksy described ('2' in the photo). It doesn't have a hex spacer section in the middle of it's length. It just has a normal hex head like many other bolts. As you suggest, the 150mm bolt is inserted from the front to the back of the car. It is pushed through holes in two lugs in the bell housing, then pushed through a hole in the engine block and screws into a female thread on the actual starter to pull it in tight.

A 7mm rod, tapped a short length at both ends, and with a nut welded to one end would do it. I don't think you can double nut it as the head seems to need to be flush with the face of the lug that the hydraulic pump bolts to.

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I took this photo for my own purposes, but then marked it up for someone on Facebook some years ago. It's the bolts that secure the bell housing to the engine. 6 is the 150mm bolt that SKP needs. 7 is the other bolt (with the hex) that Faulksy is talking about.

Bellhousing bolts labelled copy.jpg
 
If you are going to use threaded rod, tack weld a nut on the outer end so you can undo it in the normal way. If it's some abnormal setup, you will be cursed when someone (maybe yourself) has to replace a failed starter.
There must be someone in WA with this bolt???
 
Budge said:
I think you are confusing the 150mm bolt ('1' in the photo) with the other starter securing bolt that Faulksy described ('2' in the photo). It doesn't have a hex spacer section in the middle of it's length. It just has a normal hex head like many other bolts. As you suggest, the 150mm bolt is inserted from the front to the back of the car. It is pushed through holes in two lugs in the bell housing, then pushed through a hole in the engine block and screws into a female thread on the actual starter to pull it in tight.

A 7mm rod, tapped a short length at both ends, and with a nut welded to one end would do it. I don't think you can double nut it as the head seems to need to be flush with the face of the lug that the hydraulic pump bolts to.

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No, I was looking at Shane's picture with the long bolt with a hex in the middle and a short section on one side and a long section on the other side and I assumed it was the same as bolt #2 in your picture.

Your explanation clarifies the matter, thank you.

Still curious where Shane's bolt goes.

I wouldn't weld anything on that end but use faulksy's approach with a spring washer inbetween two nuts. That is solid enough to pull stuck exhaust manifold studs out usually (if they're going to come out at all). But even if it fails, at least you can take the nuts off and extract the starter with the stud (or threaded rod) attached and deal with it on the bench, I guess.

Back to our friend in need, I would suggest making a long stud is still the easiest available option if some rod of the right size can be located. Failing that, next best (easiest) would be to use some M8x1 threaded rod (or an existing bolt) and either enlarging holes and tapping for it or threading the rod/bolt down to M7.
 
David S said:
If you are going to use threaded rod, tack weld a nut on the outer end so you can undo it in the normal way. If it's some abnormal setup, you will be cursed when someone (maybe yourself) has to replace a failed starter.
There must be someone in WA with this bolt???
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Thread rod / studs are removed by using two nuts, screw one nut on, then screw a second nut against this.
Then just unscrew the first nut, it will bind against second nut and voila stud comes out
 
I read on a French forum ages ago that they were made for Citroen by a local company and it’s actually a pine tree not chevrons.
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This would be interesting. While I think it's unlikely (I've not seen these bolts on any other French car) - it's possible....I guess.

Faulksy - do you recall any other information on the fastener manufacturer from the French forum?

Regards,
Rhys
 
All this over ONE bolt!!?? Yes, it is the bolt #6 in Budge's photo.

Threading a rod and welding a nut to one end is fine..... but the only rod I can locate is 8mm...... and that doesn't go through the mounting holes on the gearbox and block. I am NOT going to grind the entire length of an 8mm shaft down to 7mm.!

I hope that DoubleChevron is posting a bolt to me.. can only be better than 3 months for parts from Europe.
I got a shipping quote yesterday to send two rear boots - 80 Euro post!!!!!! They seemed miffed that I didn't proceed.
I'll wait for my regular ( if slow ) delivery from my usual supplier.
 
skp said:
Threading a rod and welding a nut to one end is fine..... but the only rod I can locate is 8mm...... and that doesn't go through the mounting holes on the gearbox and block. I am NOT going to grind the entire length of an 8mm shaft down to 7mm.!
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If need be, just go to a tool shop with a vernier, pretty sure you'd find a long enough screwdriver with a 7mm shank. I've got a couple here that are long enough with 7mm shanks (2 different brands). Another source may be a 1/4" socket extension bar. The cheaper extension bars normally have a neat mm measurement on the shaft.
The 1/2" drive ones my local hardware keeps are 15mm shafts. They made handy driveshafts for inside extended snouts on superchargers as 15mm ID bearings are very common.
 
skp said:
All this over ONE bolt!!?? Yes, it is the bolt #6 in Budge's photo.

Threading a rod and welding a nut to one end is fine..... but the only rod I can locate is 8mm...... and that doesn't go through the mounting holes on the gearbox and block. I am NOT going to grind the entire length of an 8mm shaft down to 7mm.!

I hope that DoubleChevron is posting a bolt to me.. can only be better than 3 months for parts from Europe.
I got a shipping quote yesterday to send two rear boots - 80 Euro post!!!!!! They seemed miffed that I didn't proceed.
I'll wait for my regular ( if slow ) delivery from my usual supplier.
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80 euro is a bit of a stretch. Is it because of covid that shipping is so expensive? Or is the store that expensive?
 
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