Greetings,
I'm in need of a long bolt for a DS starter motor - M7. 150mm under the head.
Anyone have a spare?
skp
I'm in need of a long bolt for a DS starter motor - M7. 150mm under the head.
Anyone have a spare?
skp
Ds starter motor bolt!
- Thread starter skp
- Start date
Threaded rod substitute
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Hex or Alen?
If Alen you might be out of luck, if hex, you can try Searle Fasteners in Canning Vale if nothing is closer.
If Alen you might be out of luck, if hex, you can try Searle Fasteners in Canning Vale if nothing is closer.
Just went through my M7 box and the closest I've got is 80mm.
Would a stud work? It is no big deal to make one from M8x1 threaded rod (which you would definitely find at Searle if not at Bunnings but Searle might have it in a higher grade) with a M7 die.
I could also make you one on the lathe but that is more involved.
Would a stud work? It is no big deal to make one from M8x1 threaded rod (which you would definitely find at Searle if not at Bunnings but Searle might have it in a higher grade) with a M7 die.
I could also make you one on the lathe but that is more involved.
In fact, the more I think about it the more I think that I would get a M8x1 bolt of the right length wherever you can (Searle or any decent bolt place will have them) and recut the thread to M7. It's the same pitch (1mm - confirm?) so the thread will go clean on top of the old one. Just file down the M8 crests to the M7 correct diameter and put a generous chamfer on the end to start the die easily, lube up and go to town.
If the M8 shank is too thick, you might have to file it down a bit though.
If the M8 shank is too thick, you might have to file it down a bit though.
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Rods of 500mm and 1000mm and longer are more expensive due to size. Grade 2 titanium threaded rod. Other sizes available.www.ebay.com.au
Are you sure on the size? I don't have anything here M7 x 1.0 x 150
I though it was a bit strange too but then again, we're talking DS here. M8 would be what I would have guessed. Maybe it's a M8x1 which could look like it is M7?
The earlier DSs had three different pitch 5mm bolts just to make life easy.
When I got my DS one of the front bumper bolts was missing. Thought I'd just replace it out of my nut and bolt collection. Nope, nope, nope, WTF?
A quick Google search revealed they are 9mm thread. Even my nut and bolt shop went huh?
I didn't try Bunnings.
Yeah, I am starting to believe it was not the advanced designs that bankrupted Citroen but the senseless myriad of fasteners used. Or maybe they were buying whatever they could lay hands on but then imagine the owners' frustration when they had to chase some obscure thread size and pitch fastener to fix some minor problem.
I don't think you would find a M9 thread anywhere. Maybe some very specialised shop overseas (I would try some shops in the US I have used before) but if not really critical, I would just change the thread to something common with appropriate specs. Bumper for instance is just stupid. Anything between M6 and M8 would be more than plenty good. If it was a head bolt or conrod or mains or whatever like that I would think about it and if it was too hard to get the hardware, I would go one size up and get something standard (still metric) that you can get in any quality you want from the usual suspects.
Renault has used extensively M7 bolts in cast alloy blocks and such and they inevitably end up rusted in and snap when you try to replace the water pump for instance. To add insult, they are rather long and being a fine thread, I think the recipe for disaster is satisfied. M6 would have done a fine job, M8 and coarse pitch (say 1.25 or even 1.5) would have been great. Yes, it's a busy spot in the casting but that don't help when you try to drill out the M7 stubs left behind. OTOH they did probably save 1cent per car using M7 fasteners everywhere.
I don't think you would find a M9 thread anywhere. Maybe some very specialised shop overseas (I would try some shops in the US I have used before) but if not really critical, I would just change the thread to something common with appropriate specs. Bumper for instance is just stupid. Anything between M6 and M8 would be more than plenty good. If it was a head bolt or conrod or mains or whatever like that I would think about it and if it was too hard to get the hardware, I would go one size up and get something standard (still metric) that you can get in any quality you want from the usual suspects.
Renault has used extensively M7 bolts in cast alloy blocks and such and they inevitably end up rusted in and snap when you try to replace the water pump for instance. To add insult, they are rather long and being a fine thread, I think the recipe for disaster is satisfied. M6 would have done a fine job, M8 and coarse pitch (say 1.25 or even 1.5) would have been great. Yes, it's a busy spot in the casting but that don't help when you try to drill out the M7 stubs left behind. OTOH they did probably save 1cent per car using M7 fasteners everywhere.
The citroen fasteners are made by Citroen. They are fantastic quality. The reason for differences is the standards changed over time. For example M5 x 0.75 was superseded by M5 x 0.8 towards the end of DS production.
I didn't mean the M7 size. that is plenty strong enough for the starter. I mean i have M7 x 1.0 x 160 (CX starter bolt with built in stud standoff) .... and much smaller.
and look at that, there is a M7 x 1.0 x 150 bolt there. Its probably also used on CX's.
they are really good quality fasteners. That citroen symbol is cast into the head of a lot of them.
I didn't mean the M7 size. that is plenty strong enough for the starter. I mean i have M7 x 1.0 x 160 (CX starter bolt with built in stud standoff) .... and much smaller.
and look at that, there is a M7 x 1.0 x 150 bolt there. Its probably also used on CX's.
they are really good quality fasteners. That citroen symbol is cast into the head of a lot of them.
Cast, I don't think so. Stamped maybe?
Well, then my suspicion is even closer to reality then. To put so much money into making your own fasteners is just lunacy. But I do get it. It was the done thing at some point in time. BMW had all their hardware stamped all over everything before the war, but that was before the war. Still, baffling to think they did that for machines they were shortly after sending to be destroyed on the front. The brits I hear were hand finishing the paint on Spitfires. Little wonder all of them lost to the Russians and Americans who probably cared very little what their hardware looked like as long as it worked.
Your collection of M7 bolts rivals mine, but I don't have bolts that long. I do however have something you don't. Socket (alen) heads.
Well, then my suspicion is even closer to reality then. To put so much money into making your own fasteners is just lunacy. But I do get it. It was the done thing at some point in time. BMW had all their hardware stamped all over everything before the war, but that was before the war. Still, baffling to think they did that for machines they were shortly after sending to be destroyed on the front. The brits I hear were hand finishing the paint on Spitfires. Little wonder all of them lost to the Russians and Americans who probably cared very little what their hardware looked like as long as it worked.
Your collection of M7 bolts rivals mine, but I don't have bolts that long. I do however have something you don't. Socket (alen) heads.
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.
That said, the starter motor bolt under the hydraulic pump is a very long stud with a 25mm hex section about 15mm from the end like the one in Shane’s photo.
Mine sheared at the hex when trying to undo it. Had to make up a substitute by drilling and threading the hex section and screwing in an M7 bolt with a long shank
That said, the starter motor bolt under the hydraulic pump is a very long stud with a 25mm hex section about 15mm from the end like the one in Shane’s photo.
Mine sheared at the hex when trying to undo it. Had to make up a substitute by drilling and threading the hex section and screwing in an M7 bolt with a long shank
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You mean you drilled into the hex section and extracted the remains or you drilled into the hex section and threaded that? Because the hex section is very short, I am not even sure you can run a tap into a hole that short.
I asked because in Shane's picture the hex section seems to be just the normal thickness of any hex head, say 5mm?
Well, seems to be an interesting bolt!
I've already printed and framed a photo of it for my garage wall.