Hiya folks, that's right, you guessed it, I'm back to bother you some more!

Just finally getting my 94 850 buttoned up after taking care of the myriad of problems I inherited from the previous owner, and have a few miscellaneous questions for you Volvo experts.

1. Is a little bit of lateral movement of the timing belt on the gears a huge issue? I noticed this while the engine was idling after my test drive, making sure everything I have done in the past few weeks is working properly. The movement is pretty small, but it is definitely there. Don't feel like it's an issue, but wanted to make sure. Interference motors scare the crap out of me, and this is my first. It can be seen in the following video:



2. Does anyone happen to know the threading and length for the main timing belt cover bolt? I seem to have misplaced the bolt baggie for the timing belt/tensioner job, and that was the last bolt in it. My guess is M8 on the thread, but I want to be sure.


3. I wanted to clean up and regrease the brake caliper slide pins before I got the car on the road (there was some uneven pad wear, though the pads all have a good amount of meat on them still), and it seems that the slide pins in the front calipers are not the 7mm hex that I've been reading about everywhere. In fact, none of my metric hex bits fit. The 5mm is slightly too small, and the 6mm is slightly too large. Were there perhaps any 850 models that used imperial slide pins? If not, any ideas as to what's up in my case? I don't actually have an imperial hex bit set, so I'll have to go buy some tomorrow after class.

 

As long as the belt not coming off either edge it should be fine.

If you can't get a bolt locally, I have one I can send you but don't know it's size. Our S70 has electrical tape over the top of the cover, no bolt because the bolt hole is broken.

 

Cool, good to know. Thank you for the offer on the bolt, I actually ended up finding the baggie when I was cleaning up my work area.

Still a little stumped on the caliper slide pins, will explore further next weekend when I have time to work on the car some more. Hopefully someone will chime in with some insight before then.

 

On the metric / imperial brake question, I don't know.

But I would feel pretty confident from my experience with cars in general saying it has to be metric unless someone screwed it up and retreaded it SAE or jammed an SAE bolt in there.

The brakes especially, if it came with metric should always remain metric even from an aftermarket re-builder. I have seen where they have gone from one size six point bolt head to a different size head or to an internal hex or something along those lines but I haven't seen any re-builder change from metric to SAE or SAE to metric. If they are stripped out there are oversize replacements available but those should also be metric. They are like the oversize oil drain plugs where they cut into what's left.

This odd size, is it the same on the other side of the vehicle ??


(This isn't for a Volvo)
If you see one of these it's the easy repair and you want to be careful when reinstalling as it could be only one bolt on one side or both or .... and it needs to go back into the same hole it came out of. I prefer to helicoil them since it's back to stock but it's more work.

 

That was my first inclination as well: the previous owner stripped the old pin, and jammed whatever was closest that he had on hand in there. However, after your suggestion, I went around and checked all 4 front caliper bolts and the story's the same all round: 5mm slightly too small, 6mm slightly too large.

I'm at a loss, but I think it's going to have to come down to getting my hands on an SAE hex set and pulling the calipers off. Will report back what I find.

 

It's been raining for a couple days so I haven't been out to check mine yet. Are we talking a regular six sided bolt a socket would fit over or an allen or torx head where it's recessed into the head like in my photo ??

Are you trying to fit an "allen" wrench into them or a "Torx" ??



These are the correct 850 pins. They should be 7mm allen.

 

It is an allen type head as far as I can tell. I stuck my head in the wheel well to look at the bolt head, and it didn't look like Torx to me. It is possible that I saw wrong in the weird light. I also recall every search result on the matter turning up that the bolt should have a 7mm allen head.

 

Well, I guess you have a problem. I did some research (still raining so I can't get under mine) and it seems it is a 7mm allen wrench that is supposed to fit.



Photo from someone's write up for front brakes.



Don't know what else to tell you except to get it in the air with a light and get a good eye on it and see what you have.

I think that picture in my previous post that I pulled from a parts store is a generic picture and NOT the actual product for an 850, sorry.

 

I'll tell you that, without a doubt in my mind, it's supposed to be a 7mm allen. It's possible that it's either standard or the mysterious 5.5mm allen that I have in my tool set. I have a 4.5mm as well. Weird stuff.

 

Yep, the plan is to have at it this coming weekend. The brakes work fine, and the calipers don't stick as far as I can tell, so we'll see what's up. I'll report back what I find.