Truma Mover II Version M1 missing bolts

[BrownhillsBob]

I have an Elddis Avante 362 with a Truma Mover II Version M1.
On returning from my last holiday I found that there was about an inch play in the off-side roller (the whole part that clamps against the wheel), On comparing with the near-side I found that two bolts were missing (these were missing from the back of the unit as you look at it).
I have made up two bolts myself but would like to replace with original if possible.
After contacting Truma, Derby, they gave me the nearest authorised dealer and I took a bolt off the unit to show them.
They did not have any in stock and I asked if they could order two from Truma.
The caravan is 2005 manufacture, and the Truma mover I am not sure how old it is but the person at the dealers said 'Oh, its an old one'.
The bolts are 25mm in length, the thread extends approx 10mm from the tip, then there is 8mm without thread that extends to the bolt head.
The reason for the unthreaded part is so that the bolt can be tightened without locking the moving parts together (I did try a fully threaded bolt and it just locks it solid).
I have not heard from the dealer yet and I am not holding much hope in getting replacements, unless of course, someone out there knows better!

 

[Sproket]

Hi Bob
The other option woild be to get a longer one that has got the same thread but with a shoulder on, with a die of the correct size the thread can be run further down the shank so that you are left with your required length of shoulder & then cut the bolt to length,

What is the size of the thread on the bolt that you are looking for ??

 

[Dustydog]

Hi Bob
Surely Truma can post you new bolts?

FIL lost a roller a few years ago . Truma posted him a new replacement with a circlip that had been missed at the factory.
I suggest when you fit tbe new bolts you thoughly clean all sufaces and use a thread adhesive like Loctite.

 

[hortimech]

Hi, Just a bit of information first, a 'bolt' that is threaded all the way to the head is actually called a setscrew, to be a bolt it must have an unthreaded part of the shank.
So you have numerous options here, get hold a die and thread a bolt to your sample as suggested above, Try your local engineering supplier and see if they can help with a new bolt, you may find that a washer or two will take up the slack.
Failing all else, use a setscrew, tighten this up until the mover just locks, then put another nut on the setscrew and screw it down to the locked nut, hold the second nut with one spanner and then undo the original nut, this will tighten it against the second nut locking them to the setscrew but allowing the mover to move as required. You may have to play about to get the just the right tension

 

[WatsonJohnG]

.
Failing all else, use a setscrew, tighten this up until the mover just locks, then put another nut on the setscrew and screw it down to the locked nut, hold the second nut with one spanner and then undo the original nut, this will tighten it against the second nut locking them to the setscrew but allowing the mover to move as required. You may have to play about to get the just the right tension

I was thinking along those lines but wodered about using a self lock nut

 

[BrownhillsBob]

Firsty, thank you all for prompt replies.
The bolts I have made had longer unthreaded and threaded sections than needed.
I cut bolt thread to required length and packed with washers to get correct unthreaded length.
I have used Loctite on threads on bolts I have fitted.
I am sure what I have done will do the job but if possible I will get original parts to fit.
Thank you Hortimech for information regarding 'setscrews' and 'bolts' I am wiser for your knowledge.
Yes, Dustydog, I wholeheartedly agree with you that Truma should be able to replace these parts but I did phone them and the lady that answered the phone said they don't do them, and all she could do is give me the name of my nearest dealer that supplies and fits Truma movers. I got the impression that the number for Truma in Derby is offices only but surely they have stores and/or suppliers that I could contact to obtain bolts, but invariably if you cannot get past the receptionist you don't stand a chance.
Just two 25mm bolts and Truma cannot deliver.

 

[otherclive]

If you dont have a local engineering supplies shop, or Halfords dont stock a suitable bolt, I would try the internet as there are lots of fastener suppliers out there. I use them for sourcing Japanese spec bolts for my Pajero. You can generally buy in small quantities. Make sure you get the correct strength as there are variations in tensile strength of bolts but if you look on the internet there are a lot of sites that show you how to tell what strength the various bolts are. Just look at the heads of the bolts that are still in situ.
But I am somewhat shocked that Truma cannot supply you or at least tell you what the specification is.

Just by Googling 'Bolt strength chart' this link came up;

http://www.boltdepot.com/fastener-information/Materials-and-Grades/Bolt-Grade-Chart.aspx

 

[BrownhillsBob]

Thanks for pic Hortimech.
I have two setscrews and nylock nuts that I can use should I need any more. Because of the extra length needed for the locknut I can use them if needed on two out of the eight bolts.