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Steve in Cairns
16th January 2015, 10:10 AM
Morning.
I am trying to put my series 2a petrol engine back together and need some help.
1) the nuts I an using to hold the connecting rod caps ars a locking nut, not nylox, and are stiff to turn. When I torque them up to the correct setting I am unable to turn the crank. Should I be able to turn the crank and how do I allow for the torque of the nuts.
1) the cam shaft tappers say to put the roller in with the chamfered side facing front. My rollers have both sides chamfered, can they go in any way?

Thanks

Steve

mick88
16th January 2015, 11:11 AM
Morning.
I am trying to put my series 2a petrol engine back together and need some help.
1) the nuts I an using to hold the connecting rod caps ars a locking nut, not nylox, and are stiff to turn. When I torque them up to the correct setting I am unable to turn the crank. Should I be able to turn the crank and how do I allow for the torque of the nuts.
1) the cam shaft tappers say to put the roller in with the chamfered side facing front. My rollers have both sides chamfered, can they go in any way?

Thanks

Steve


Steve
I only put a two and a quarter back together a few weeks back and I used new nuts on the con rod caps. The locking nuts are not available and are replaced with a straight nut, High Tensile "Grade 8". Once tensioned to the correct torque setting the rod should still move freely on the journal. Stating the obvious but have you got the correct size bearing caps? Are they fitted correctly into their locating notches? If you are re-using the old nuts perhaps a dash of "service removable" Loctite would give you peace of mind.
As for the cam followers/rollers, I replaced mine as they were originally fitted. I do recall that one side of the roller had a larger indentation but I am not sure if it went to the front or rear. Maybe they were changed to chamfers on both sides so they can be fitted either way.


Cheers and good luck,
Mick.

Steve in Cairns
18th January 2015, 04:45 PM
Thanks.

Still not turning.

Changed the nuts, the bearings caps are what was on before stripping and things seemed ok then. I have put in new Pistons and rings, do these take time to bed in ?

Cheers
Steve.

JDNSW
18th January 2015, 05:18 PM
If it will not turn with the new bearings, there are several possibilities - the big end caps are not on their original rods, or have been turned 180 degrees; bearing shells are not seated in their notches; dirt or lint behind the shells; shaft and bearings not assembled oily; wrong size bearings; bent con rod or possibly conrods in wrong hole or turned 180 degrees; + probably a few I have not thought of.

Can you confirm that it turned before torquing up the nuts? i.e. it is not the pistons that won't move.

John

Steve in Cairns
18th January 2015, 06:50 PM
Will try in the morning with the nuts lose to see if it turns
Cheers
Steve

rangieman
18th January 2015, 08:54 PM
Can also be oil gunge build up on the rods and bearing caps . Which can reduce the bearing tolerence to crank . Clean the rod and big end cap surface before refitting bearings;)

mick88
18th January 2015, 09:02 PM
If you have new rings it will be tight to turn over by hand! Make sure you have plenty of oil in the cylinders.
Good luck.


Cheers, Mick.

Steve in Cairns
19th January 2015, 07:20 PM
Loosend the bolts and it was still hard to turn over, I am hoping that it is just the new rings - fingers crossed

Steve

harry
20th January 2015, 09:13 PM
Loosend the bolts and it was still hard to turn over, I am hoping that it is just the new rings - fingers crossed

Steve


was it hard to turn the crank before you fitted the conrods?

67hardtop
21st January 2015, 11:17 AM
Hi, just wondering, did u clean the ring grooves out before fitting new rings to the pistons? This can cause the pistons to be very tight in the bores. Also check the ring gaps in the bores before fitting to the pistons. Hope this helps

Cheers Rod:wasntme:

Busted Syncro
21st January 2015, 02:53 PM
G'day,
Can I suggest that you go to repco and buy some plastigauge and check the bearing clearance on your big ends and mains if you have replaced them as well. It look like a process of elimination here. I always check the ring gap in the bore before I fit new rings to be sure they are the right size. Also check the piston to bore clearance as well. (An race engine builder taught me to measure everything as you rebuild an engine.)
Best regards Chris

Steve in Cairns
26th February 2015, 04:32 PM
After some time off, health + work, I have managed to get all the bits together in one. She turns over on the starter motor quite nicely.



Thanksto you all for your help.