Speedy engine big end bolts

[Ian Williams]

Yes Steve that sounds like the issue I had, as I recall the drilling up the centre was too small as well, maybe 3/16" I opened mine out.

[Steve Berg]

Hi Ian

In the meanwhile I have bought a 1 1/2" pressure-fed Phoenix crankshaft and rods through David Cochrane :-) Phoenix just happened to have one on the shelf for an order which had been cancelled.

Did your crankshaft also come with little grub screws to close off the oilways in the crank webs?
If so how did you fix them in place? Loctite? 
Similarly, how did you fix the big-end bolts? Are yours also ARP2000 bolts?
What is the recommended torque for the big-end bolts?
ARP recommend their proprietary oil when tightening the bolts so as to achieve consistent torque and bolt stretch values. This is new stuff for me. what do you know about it?

The starter dog that Phoenix delivered turned out to be completely wrong and presumably meant for a different engine layout altogether. I expect to get a correct one hopefully in reasonable time.

The above questions have also been sent to Phoenix but I was wondering what your experience with these things is.

Best wishes
Steve

[Ian Williams]

Steve

"Did your crankshaft also come with little grub screws to close off the oilways in the crank webs?" - Yes

"If so how did you fix them in place? Loctite?" - Yes

"Similarly, how did you fix the big-end bolts? Are yours also ARP2000 bolts?" - No need for any loctite if correctly torqued

"What is the recommended torque for the big-end bolts?" - From memory 35ft/lbs

"ARP recommend their proprietary oil when tightening the bolts so as to achieve consistent torque and bolt stretch values. This is new stuff for me. what do you know about it?" - I listened to ARP, after all they make the things so have a vested interest in giving sound advice.

"The starter dog that Phoenix delivered turned out to be completely wrong and presumably meant for a different engine layout altogether. I expect to get a correct one hopefully in reasonable time." - Yes that was my experience, the Phoenix dog is not correct for an original pressure fed nose cone.

[Bill Sheehan]

I found no problems or surprises other than the starter dog, my car uses the original 3/8" lift cam and everything cleared when assembled. The issues were the that oil ways within the dog were too small for my liking and the cross drilling was in the wrong place, the dog is hardened so a drill bit with tungsten carbide tip is required to open the holes out. Probably with hindsight, had I been aware of this when I ordered Phoenix could have made the starter dog to suit my engine. I believe the issue stems from the fact most pressure fed cranks are built into non original engines using a completely different oil bottle and seal arrangement at the front of the engine.

Ian, I have been in touch with Marc Taylor of Phoenix Crankshafts and he very kindly sent me a drawing of the starter dog that they make based on a 30 year old design they received from an A7 owner, Brian King (are you out there anywhere Brian?). On this drawing the cross hole for crankshaft lubrication is positioned 13/16" from the external face of the 1 1/2" AF nut whereas on my starter dog the cross hole is 1 1/8" from the face of the nut. I guess this is the same problem that you faced. The diameter of the hole is 3/16" as on the drawing.
Marc says it would be possible to relocate the cross hole to fit.

[Steve Berg]

Steve

"Did your crankshaft also come with little grub screws to close off the oilways in the crank webs?" - Yes

"If so how did you fix them in place? Loctite?" - Yes

"Similarly, how did you fix the big-end bolts? Are yours also ARP2000 bolts?" - No need for any loctite if correctly torqued

"What is the recommended torque for the big-end bolts?" - From memory 35ft/lbs

"ARP recommend their proprietary oil when tightening the bolts so as to achieve consistent torque and bolt stretch values. This is new stuff for me. what do you know about it?" - I listened to ARP, after all they make the things so have a vested interest in giving sound advice.

"The starter dog that Phoenix delivered turned out to be completely wrong and presumably meant for a different engine layout altogether. I expect to get a correct one hopefully in reasonable time." - Yes that was my experience, the Phoenix dog is not correct for an original pressure fed nose cone.

Thanks, Ian, for your feedback on the Phoenix crank.
May I ask your opinion concerning balancing of con-rod and flywheel?
The old crank and flywheel setup was balanced over 10 years ago but I believe this could only have been static balancing since the crank itself was not modified, only new holes in the flywheel.
Would you recommend having the balance rechecked with the new Phoenix crank, which I presume will have been be balanced judging by the grinding marks in places, and the old flywheel?
I know too little about this and would be grateful for your opinion. Or anyone elses too.
Thank you!

[Ian Williams]

I am a firm believer in balancing Steve, in my experience it makes a much smoother engine and has to reduce stresses, I would have the whole assembly rechecked dynamically.

[Ruairidh Dunford]

I second that.

Dynamically balance the crank and complete flywheel assembly less the centre plate.

End to end balance the rods - do this and you won’t regret it.

[Steve Berg]

Thanks, Ian and Ruairidh, for your encouragement.
Anything that makes the engine quieter is worth doing.
Based on that I had a brief look at the clutch levers today and get the impression that one of them is slightly different from the other two. For a start it is about 1mm shorter. So I'll dismantle the rear clutch assembly and take a closer look. Seems to me, if this is part of the balanced assembly then It should be as "right" as possible.

Ruairidh, I saw that you posted illustrated instructions in the old forum on how to dismantle the clutch and those trying mousetrap springs. Unfortunately the pictures, I think in Photobucket, don't show up on my screen. Is this information available elsewhere?

[Colin Wilks]

I am resurrecting this thread as Steve's initial query is exactly the problem I have. I am fitting a 1 1/2" John Barlow crank and reusing my original Austin rods (which have the green light from Nick Turley). I am not going to reuse the big end bolts which I am sure have been torqued up on several previous occasions so am wanting a set of bolts as in Steve's photograph. As he says these have a pin perpendicular to the shaft to locate the chamfer and have much meatier heads than the chamfered but pinless jobs which I think may still be available, but which are probably not robust enough to drill and pin.

Has anybody found a supply of these bolts and if not what cunning alternatives can people suggest?

Colin

[Steve Jones]

The problem with just using a 5/16" bolt and modifying it is that A7 big end bolts are fitted bolts. That means they are of a very slightly larger diameter when compared with an ordinary 5/16" bolt and therefore the clearance between the bolt and the holes in the rod/cap is reduced. Try fitting a proper big end bolt and a normal 5/16" bolt through a rod & cap and compare the fit of the two.

However, the slightly increased diameter of a M8 bolt over a 5/16" bolt overcomes this and opens up a much larger range of bolts to choose from. In an ideal world, I'd hope you find a set of unused, correct, big end bolts, Colin, but I fear they might be a bit like trying to find the Holy Grail. If that does prove to be the case then a set of quality M8 cap heads of appropriate dimensions might be the best point to start from if you have to modify a standard bolt.

I appreciate the purists might shout and scream but my primary aim would always be that the engine holds together and anyway, the above suggestion was given to me by a certain Dr. Rob and if it's good enough for him, it's certainly good enough for me.

Steve