loose idler arm

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shant67
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loose idler arm

Post by shant67 »

I checked my suspension and found the idler to be loose. I have removed the idler and now should I rebuilt the one I have, or replace it with a used one? Dean sells a bushing kit $150 requires for the bushing to be honed!!! Any other option or advice is appreciated... thanks in advice
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Nissanman
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Re: loose idler arm

Post by Nissanman »

My advice is to take it to a workshop.
I had my steering and idler boxes rebuilt at my local transmission repair shop.
They had the idler shaft coated with hard chrome and honed the new bushes to suit.
It is not the sort of job that the average home mechanic can do.
Nissanman, just trying to help.
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tjp
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Re: loose idler arm

Post by tjp »

Nissanman wrote:I had my steering and idler boxes rebuilt at my local transmission repair shop.
Can we get a rough estimate of what it cost you please? Thanks either way.
My junk pile:
71 Jeep Gladiator. Restored w/#s matching engine. My WeeBeasty
70 1600 legit 2nd owner. Stroked and bored
Several salvaged w access to a barn full of parts, part cars & whole cars
......What's in the barn is for sale. What do you need?
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Nissanman
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Re: loose idler arm

Post by Nissanman »

I'm only guessing now but the hard chroming was ~$80AUD and the assembly about the same.
If you get the shop to do everything they can hone where necessary to get a nice snug fit which should last a looooong time :)
Nissanman, just trying to help.
1965 SP310 Engine No. G-93326 Car No. SP310-10817
https://photos.shutterfly.com/album/60141836519
On the road again!
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tjp
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Re: loose idler arm

Post by tjp »

Nissanman wrote:I'm only guessing now but the hard chroming was ~$80AUD and the assembly about the same.
If you get the shop to do everything they can hone where necessary to get a nice snug fit which should last a looooong time :)
Thank you
My junk pile:
71 Jeep Gladiator. Restored w/#s matching engine. My WeeBeasty
70 1600 legit 2nd owner. Stroked and bored
Several salvaged w access to a barn full of parts, part cars & whole cars
......What's in the barn is for sale. What do you need?
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Re: loose idler arm

Post by greydog »

I think Dean at Datsun Parts has a couple options including a rebuilt/exchange one as well as a shaft and bushing set. His info says to take it to a shop to have the bushing pressed in and reamed to fit the shaft.
Dan
SPL311 aka Skooter. Sold. Now wasting away in the SF area.
1990 Nissan 300zx. Sold this one too.
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exit64
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Re: loose idler arm

Post by exit64 »

I did mine at this summer. E&L Machine here in Hood River has the correct tool to hone it. I also replaced the threaded insert in the housing. It is a press fit with pins. I tapped out the pin holes and am now using set screws to hold the insert in place. Still trying to come up with a better after market oil seal. Any ideas would be appreciated.
Mike
1967.5 SPL 311-14542 Pieces-parts
1969 SRL 311-09979
1966 411 Blackbird....Stay tuned.
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Linda
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Re: loose idler arm

Post by Linda »

So I wonder if a tranny or a machine shop is better equipped to do the job? And I assume you bring the bushings in, or would they have them?

Linda
Sadly-Linda has passed away 2022. She was the 311's den mother and drove the first Rare-Parts ball joint project. RIP.
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Datrock
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Re: loose idler arm

Post by Datrock »

If you can find a semi-retired "manual lathe" operator that still does side work in his own shop then you can rebuild the old idler box with a piece of cold rolled steel and piece of bronze or a replacement bronze Garlock type bushing for the lower bushing.
I did this idler rebuild with the help of a 80+ year old lathe owner I know. I used to run manual and CNC lathes for a living but do not own one so I crunched the numbers while he pulled the levers and we made the upper threaded bushing on the first try. Any semi-retired lathe operator will have the skills to thread and he will need to undersize the shaft by a few thousands of an inch to clean up the wear spot on the lower end and to clean up the threads to take the knife edge off the worn side where the upper bushing rides against. I have also installed the kits but preferred this method and how the parts fit better than the pre-made bushing in the kits. I had to search for a good shaft when I used the kit, by rebuilding my own idler I used the worn shaft that the kit did not allow me to use unless I wanted a sloppy fit or find a better condition shaft.
Your machinist of choice will need to dial the shaft in for minimal run out and when the machining process starts he needs to remove the material on the shaft in one step or if he has to two step the part then re-dial it in. He should have a machinists ready reference book that has the numbers that are needed for the 1x12 thread pitch that he will be working with. He will need to undersize the 1x12 pitch numbers to make this work.
Once the worn shaft is cleaned up then the bushing will have to be made to match the undersized 1x12 pitch. We chucked the piece of bar stock in his old LeBlonde lathe and machined the face then the outer diameter, drilled the bore, ran a boring bar in the bore to the new minor diameter then proceeded to thread the bushing to it's new undersized 1x12 pitch. Once the bushing gets close finish size we used the re-machined shaft as the test plug. We parted the bushing from the lathe with a groove tool, flipping the part over and second siding the back side of the bushing to length will also work fine.
The lower bushing was also machined from a solid piece of bronze then grease grooved. I honed it once it was press fit into the box. The press fit will transfer to the bore on bronze so if the bushing to shaft fitment feels fine before installing it into the housing don't be surprised it it to tight after installed.
As for the tapered end of the idler shaft, the re-machining did not remove material from the tapered area where the idler arm attached to.
Then as Mike mentioned fasten the threaded bushing into the housing either by using a set screw, plug, or tack weld... I used a tack weld in two spots.... Bill
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Re: loose idler arm

Post by greydog »

Lotta cut to fit there Bill. As you said, it's gonna take a person with skill and knowledge to make this work correctly. That probably means an older guy or small shop.
I've not had one of these apart but looking at your description, could the shaft be built up (perhaps chromed) and then ground to factory spec? Then a new bushing pressed in and honed? Seems like that would eliminate undertsiziing the shaft and recutting threads. This process would not be less expensive than your method but, if an owner preferred, could it be done as I'm thinking?
Dan
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1990 Nissan 300zx. Sold this one too.
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Datrock
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Re: loose idler arm

Post by Datrock »

Hi Dan, yes the lower bushing area could be built up with hard chrome and reground back to original since a skim cut should clean up the worn area. As for the upper threaded area, I would imagine that a hard chrome layer will build it up but re-cutting the threads in the chrome is beyond my knowledge. The tapered end will have to be shielded during the chrome process to keep the tapered spline and threads from filling up with chrome.
You do know that the cost just skyrocketed :D :D :D ...I was fortunate to make the lower bushing when I was still punching the clock at Linn Gear, the upper bushings time was bartered for with extra roadster parts and the material was used from bar stock ends that were basically scrap.
Now if I only had a lathe....LOL...
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Re: loose idler arm

Post by Linda »

Let's take up a collection and get Bill a lathe for Christmas, then he could rebuild everyone's idler boxes!

Linda :smt111
Sadly-Linda has passed away 2022. She was the 311's den mother and drove the first Rare-Parts ball joint project. RIP.
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Re: loose idler arm

Post by greydog »

Do the threads have to be recut? If not, they could mask both the threads and the taper.

Linda's right Bill, be careful what you wish for.

Thanks for the info.
Dan
SPL311 aka Skooter. Sold. Now wasting away in the SF area.
1990 Nissan 300zx. Sold this one too.
2018 VW Tiguan
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exit64
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Re: loose idler arm

Post by exit64 »

I gave a high end machine shop here in HR the NOS threaded bushing before I installed it. They made drawings of it and gave me a number for a production run of starting at 25 pieces and up to 100. I could have them made with a phone call if there is enough interest. For a run of 25 they were at $50 each if I remember right. Of course they got cheaper as the quantity increased. The hard part is finding the lower brass bushing with a groove. I bought my parts from one of the vendors but I got one of the last of both of those parts. Being a cheap Datsun owner motivated me to start looking into this as I still have two more idler boxes to rebuild. PM me if anyone wants to get in on a run of threaded uppers. If I can get enough interest for 23 more I will get them made.
1967.5 SPL 311-14542 Pieces-parts
1969 SRL 311-09979
1966 411 Blackbird....Stay tuned.
1971 B110 757213 About to unleash 69 HP @6000 RPM
A carburetor man in a fuel injection world.
"Ripping the Bring* and sanding it round"
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tjp
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Re: loose idler arm

Post by tjp »

I'll be in for at least one set of this part run.
My junk pile:
71 Jeep Gladiator. Restored w/#s matching engine. My WeeBeasty
70 1600 legit 2nd owner. Stroked and bored
Several salvaged w access to a barn full of parts, part cars & whole cars
......What's in the barn is for sale. What do you need?
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