The BSA A7-A10 Forum

Technical => A7 & A10 Engine => Topic started by: RichardL on 19.02. 2014 03:36

Title: Sticky Rod
Post by: RichardL on 19.02. 2014 03:36
Gents,

Even though I want to believe what you will see in the linked video is not a problem,  I've decided I'd better take some advice before lunging ahead on this belief. What is shown is a bit of stickiness in one rod after assembly on the crank. Somewhat late in the video I've mentioned that this is in a 40 deg. F. garage,  leading to thick assembly lube, but thaat doesn't account for the single-point stickiness and difference between the rods. After shooting this video, I took the rod apart to look for anything unusal and saw nothing. If you've got two minutes to check this out, I'd appreciate any comments.

Richard L.

 http://www.youtube.com/watch?v=G8lJ8zQnXFs
Title: Re: Sticky Rod
Post by: bikerboy on 19.02. 2014 04:00
Are you saying you just bolted those rods on the crank?
Title: Re: Sticky Rod
Post by: RichardL on 19.02. 2014 05:04
I bolted the rods on after checking journal diameters being within the 30-under spec, a tiny bit of polishing the journals and a dry fit for the plastigage measurement. I think the journal could be 0.0005" out of round. I suppose that if the rod bearings were also 0.0005" out of round there could be some snugging up. I am guessting that what is happening there is not total closing-up of the clearance, or it would seem a lot more like locking up than snugging up.

For those MAP billet rods, the ARP bolts are recommended to be tightened until they stretch 0.005", or, if unable to measure stretch, then 49 ft. lb. I think I did a fair job of measureing stretch and keeping them within the 49 ft. lb. 

Richard L.
Title: Re: Sticky Rod
Post by: muskrat on 19.02. 2014 13:10
G'day Richard.
49 ft/lb seems high to me, but I've never had beautiful rods like those (and shame on you for letting them fall onto the vice like that). If the rod and journal had corresponding out of roundness it would be free for a short distance then tight the rest of the way around.
Does the tight spot disappear if the bolts are done up to 40 ft/lb? Have you tried swapping the rods over?
Cheers 
Title: Re: Sticky Rod
Post by: Briz on 19.02. 2014 14:16
That doesn't look too bad, especially given the low temperature. Try warming the rod very slightly and see if it makes a difference.
If it was a steel rod, I'd suggest giving the rod a few light hammer taps to seat the shells a bit. But be careful on ally rods! I too winced when I saw them dropping against something metal. *eek*
Title: Re: Sticky Rod
Post by: groily on 19.02. 2014 14:48
Doesn't look too bad to my eyes either Richard - the rod seems to drop smoothly when more than a few degrees off vertical - but then I can't feel it like you can. It's not 'notchy' is it? Just an unlikely thought - could it just be there's a very slight impediment caused by almost imperceptible roughness around one of the oil drillings on the journal? (I've had to chamfer them a bit before now, but only usually after regrinds.)
I was always told that a set of perfect rods on perfect journals with perfect shells should just drop gently from off-the-vertical under their own weight with some lube in the shells, but usually I've found even after regrinds that they drop a bit more easily than that (like your other one - ouch again!). Have you given the thing a blast from a hair drier or hot air gun to see if it makes a difference?
The 49 ft lbs does seem high, to Musky's point, but similar brand new rods I fitted to a 650 AMC project motor last year specified 42 ft lbs - near-double the recommended torque for the original-style rods. If yours are like mine on that engine, you literally can't see any join- line between rod and cap when the things are torqued up. They make them to altogether different (higher) standards these days - I hope!
Good luck with the rest of the (re)build!
Title: Re: Sticky Rod
Post by: RichardL on 19.02. 2014 15:22
About hitting the vice, what was really getting hit were the soft jaws made up of a couple of old aluminum pie tins. I figured the pie tins are much softer than the rods, and where the hitting was happening was floppy anyway. Nevertheless, maybe I should have been more careful or, at least, not let you see me being uncareful.

Regarding swapping the rods, "Doh!" That's a good idea and I wish I had done it before assembling the cases. But hey, why should I have thought of that, just because it is just like basic audio troubleshooting, that is, swap the cables.

Richard L.
Title: Re: Sticky Rod
Post by: RichardL on 19.02. 2014 15:47
About the torque on ARP rod bolts, please see the attached instructions from MAP Cycle. Let me scream *warn*, 49 FT. LB. IS DEFINITELY TOO MUCH FOR STANDARD ROD BOLTS which we commonly think of as torquing at 22 to 26 ft. lb. depending on who you ask.

Bill, it's not "notchy". About the join line, you're right, it virtually disappears. The landings between cap and rod are serrated to fit together uniquely and with no possible sliding about. So, if it did happen to be due to some slight rise around the oil hole would it matter in longevity. (I hate it when I'm being lazy and don't want to separate the cases again, now that the cam gear, crank hob and worm drive are all mounted. But, hey, maybe a perfect opportunity to fix helicoils. Is it Fall yet?))


Muskie, The snug spot only disappeared on real loosening.
 
I'm goind to try some heat again, now that the garage is not freezing.

Richard L.

Title: Re: Sticky Rod
Post by: groily on 19.02. 2014 17:51
If it were me .  . . and I know you're not me Richard, you're far more sensible  . . . I'd go with it as it is having got to where you are. I really don't think any harm will come of it.
Thanks for the 'cc' of the instructions that came with the rods - scary stuff about what happens if you don't do it like they say, but heck  . . . you did!
I went and bought some torque-measuring protractor device to go on a socket spanner (sorry, wrench) one time, to let me know when I'd hit x ft lbs (or metric unchristian equivalent) plus y degrees of tool-twist on top. Did all that - modern car engine iirc - and everything was fine. But it probably would have been just as fine if I hadn't bothered and hadn't bought this gizmo that I'll probably never ever use again.
I'd be very surprised if you had a problem with what you've done. A bit of care for the first few miles and I bet it will settle down beautifully. Not famous last words from a person about to be eviscerated by wiser souls, I hope!
Title: Re: Sticky Rod
Post by: RichardL on 19.02. 2014 18:46
Wellll, I didn't do it exactly as ARP recommends. I used my 2"-3" micrometer instead of this here device that they want you to use:

http://www.summitracing.com/parts/arp-100-9942?seid=srese1&gclid=COKOvLPp2LwCFStgMgodPxEASw

As for trying to get accurate torque, my torque wrench is the cheap type with a pointer. To calibrate it I measured from the center of the drive to the center of the handle. Using this measurement I  calculated (basic arithmetic) the weight that I would need to hang off the handle to generate 49 ft. Lb. Then, I filled a five-gallon bucket with the water weight I needed and hung that off the handle while the drive was clamped in the vise and recorded the reading off the graticule.

Sorry, it turned into more story than it's worth.

I'm looking forward to getting home and seeing where I stand with the warmer garage.

Richard L.
Title: Re: Sticky Rod
Post by: chaterlea25 on 19.02. 2014 19:34
Hi Richard and All,
Like the other posts I believe that your rods will be fine, assuming that you followed MAP istructions and that the shell tangs were not causing an issue
WHen the offending rod is at the tight spot have you tried pulling it side to side (rocking)?
That may cure it ???
Also check  that theres the required side clearance on the journals

I have a MAP kit to go into the RGS project whenever time permits me to get at it, I had read the instructions, but seem to remember discussion on this "high" torque value before on the forum ????

Re torqing 5 times on NEW rod bolts seems weird to my way of thinking  *conf*
Most automotive head bolts torqued as Groily described are one use items

Now a 64,000 dollar question  *help*
I have another A10 engine on the to do list which has original BSA rods and a set of new ARP bolts
What proceedure and value do I use to torque these  *????* *????*

When I was a young teen I spent a lot of time working at the local car garage,
I can well remember reground cranks being fitted and having to lever the crank round to fit the rod caps
When rebuilt these cars often had  to be towed to get the engines to turn over and start *eek* *eek*
After a while running they would loosen up and be OK
At the time I thought this was "normal"  *eek*

Regards
John
Title: Re: Sticky Rod
Post by: bsa-bill on 19.02. 2014 19:52
Quote
Re torquing 5 times on NEW rod bolts seems weird to my way of thinking

The last bolts I bought were a special batch made for a certain Mr Cheyne who some of you may know.(may even be here)
They had a higher torque figure than normal (sorry can't recall at the mo) and required to be torqued up to the same figure three times, also supplied with stretch measurement which I checked after torquing and found to be spot on
Title: Re: Sticky Rod
Post by: Briz on 19.02. 2014 20:25
The torquing method they recommend is normal for ARP fasteners. It says the same on the ARP site.
These, and most other billet rods use 3/8unf bolts. The stock ones are 5/16" cycle thread. Hence the different torque requirements.
If you can measure bolt-stretch, thats the best way. A mic is fine, you dont need the expensive dial tool.
Title: Re: Sticky Rod
Post by: Brian on 19.02. 2014 20:40
John, ARP recommend 28 ft lbs for their bolts in standard BSA rods.

I tightened mine twice as per their recommendation and then the final time to the 28. The multiple tightening thing seems odd to me, I have never run across it before.

I had a few e-mails back and forth from ARP's tech department before they recommended the 28 lbs, the bolts came with a slip of paper recommending a much higher figure, cant remember exactly what it said but it was obviously way to high for std rods.

I did use loctite, against their recommendation.
Title: Re: Sticky Rod
Post by: chaterlea25 on 19.02. 2014 21:20
Hi Briz, Brian
Thanks for the quick replies  *smiley4*
28 ft lbs it is then, I can cross check bolt stretch as well

Its taking a while longer than I thought to get back onto the workshop after my op on New Years eve
I can manage an hour or two per day this week but its still painful
The work load has backed up a lot  *sad2* but bugger all I can do about it

Cheers
John
Title: Re: Sticky Rod
Post by: RichardL on 19.02. 2014 21:52
This may be interesting in terms of 5/16" vs. 3/8" ARP bolts:
Title: Re: Sticky Rod
Post by: chaterlea25 on 19.02. 2014 23:39
Hi Richard
Thanks for the pic, I have saved ARP site on the PC

Regards
John
Title: Re: Sticky Rod
Post by: Topdad on 20.02. 2014 14:39
Richard bringing this down to a more basic level , those rods are something else , - no little end bush? Have to admit i'm green with envy and will definately invest in them when I rebuild my motor . Must say like Musky I did cringe at the clonk and would have very worried had it been with old rods !
John good to hear you're on the road to recovery ,at least you are listening to your body and so get yourself right steadily. Yes I to remember having to tow cars to get 'em going after a crank exchange ,a certain bedford dormobile wouldn't even move til I used my landie in four wheel to get it turning over once started no probs and the body rotted off it ( typical vauxhall/ bedford rust bucket )whilst the motor was still fine , best wishes BobH.
Title: Re: Sticky Rod
Post by: RichardL on 20.02. 2014 16:12
Bob, et al,
 
MAP Cycle's new A10 rods are steel "H"-beam design, with bushing. SRM has billet rods without bushings. You may not recall this story, but I got those rods free after a machinist I used made my stock rods unusable by honing the housing without milling the landings.

Now, as for abuse by dropping, I admit I should have been more careful, but it seems I will need to get a Rockwell hardness test done on my pie-tin soft jaws and on the rods before I will live it down. Even then, I'll be in trouble for the dimple left by the hardness tester. (I will never admit to the shallow crescent-shaped scrape near the large end where one rod came in contact with the skirt after the last rebuild. No, you will have to beat that confession out of me. Thankfully, 3,700 miles later, it seems not to matter, but skirts will be relieved this time. Oh sh*'t, the backspace key seems to be broken.)

I feel I am going to have an obsessive compulsive episode and split my cases again to further investigate the sticky rod, as warmer weather did not help. This is not disregard to the good advice suggesting it is probabaly OK, but just because 3 or 4 hours lost now is much better than 75 hours and $$$ lost later. Here's my warning to you: "I'll keep you posted."

Richard L.

Title: Re: Sticky Rod
Post by: RichardL on 22.02. 2014 21:21
Gents,

As I thought, I was unable to fight the urge to split the cases and take another look at the sticky rod. I think the problem might be similar to what Groily described, though, not a "roughness" around the oil hole but more like an uplift. In one of the attached pictures you can see a streak through the coating down the center of each bearing half (in brand new shells). As I understand it, the shells are thicker 90 deg. from the parting line, which would explain why the streak does not go all the way around.   In the other photo, you see the line of light on the bearing appear to curve around the oil hole. I think this curving may be showing the uplift around the lip of the hole. 

Assuming my theory is right, I have two questions:

1. What's the best way to remove the uplift? I was thinking 800 wet paper wrapped around a jeweler's file followed by 1000. Is there a better approach? I am sort of nervous to go in there with a drill bit that is big enough to do the job.

2. Do the scuffs in the bearing coating matter when I reassemble? I can just barely feel them with a finger nail.

For those who said the engine would be fine if left alone, I think I agree.  The result would have been  the very slight grooving in the bearing which would not have affected overall performance.


Looking forward to your comments.

Richard L.
Title: Re: Sticky Rod
Post by: Briz on 22.02. 2014 22:45
If its a burr you can feel with your finger, a couple of careful passes with a dead-smooth file before the fine emery would be how I'd do it.
I dont think you'll have a problem using those shells.
Title: Re: Sticky Rod
Post by: RichardL on 23.02. 2014 00:02
Briz,

That seemed like the perfect advice. so I've gone ahead with it: jeweler's file, followed by 800 wet, followed by 1000 wet, followed by buffing with dremel. Looks like it got it, but the rod is not back on the crank yet. Keep you posted. Thanks.

Richard L.
Title: Re: Sticky Rod
Post by: jachenbach on 23.02. 2014 13:33
Nothing at all wrong with the old beam type torque wrench. I've got beam, clicker and electronic ones. Clickers and electronics are supposed to be calibrated now and then. Beam types seem to last forever. I suspect they may even be more accurate as you can see clearly when you're approaching the desired torque and stop at it, whereas you can easily surpass it with a more expensive unit.
Title: Re: Sticky Rod
Post by: RichardL on 26.03. 2014 05:03
At the risk of becoming known as "Mr. Sticky", I thought I should share this video showing the "after" after dressing-down the oil holes in the journal, cleaning up the bearing housing and flipping the rod around on the journal. This video of course precedes the next episode in the "Sticky" series, "Sticky Crank". I thank all for sticking with me through these sticky issues and giving good advice, all around, rather than telling me to stick it.

http://youtu.be/G8jcmoPy6dA

Richard L.
Title: Re: Sticky Rod
Post by: muskrat on 26.03. 2014 06:23
Your a real stickler  *smile*.
Looks like you'd have the cleanest sludge trap around by the number of center pops around the plug.
Cheers
Title: Re: Sticky Rod
Post by: duTch on 26.03. 2014 09:24
 I guess that you haven't screwed the sludge plug in so far as to restrict the oil flow...?
 When I did mine, ol' mate said just screw it in so it's flush...?

 I'll also have a closer look at the how to play the banjo on the end, he/they make it look so easy...dangit!!!
Title: Re: Sticky Rod
Post by: RichardL on 26.03. 2014 11:06
The dimples you can see are by P.O.s. I used loctite and really small dimples. Plugs are flush or very close. I know oil goes in because I pumped some in through the timing-side journal.

Scratching my head regarding "banjo", but I will be sure to laugh when I figure it out.

Richard L.
Title: Re: Sticky Rod
Post by: duTch on 26.03. 2014 12:57

Quote
Scratching my head regarding "banjo", but I will be sure to laugh when I figure it out.

 At the end of the uTube, it goes on to demo how to play a Banjo....-least in my world it does...maybe some of Wozzas Deliverance medication blew my way. *conf* *smile*
Title: Re: Sticky Rod
Post by: chaterlea25 on 26.03. 2014 21:56
Hi All
This is what comes up at the end of Richards clip here in Ireland ?????

https://www.youtube.com/watch?v=AFgmrr6yu3E

John
Title: Re: Sticky Rod
Post by: duTch on 27.03. 2014 09:01

 Ok you  win- for now, this time it had Earth, Wind and Fire, but somehow I ended up with http://www.youtube.com/watch?v=briyHuefm8Q&feature=youtu.be (http://www.youtube.com/watch?v=briyHuefm8Q&feature=youtu.be)

 Nothin' like yours either John....!