The following warnings occurred:
Warning [2] Undefined variable $search_thread - Line: 60 - File: showthread.php(1617) : eval()'d code PHP 8.1.28 (Linux)
File Line Function
/inc/class_error.php 153 errorHandler->error
/showthread.php(1617) : eval()'d code 60 errorHandler->error_callback
/showthread.php 1617 eval




Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Another disturbing noise from Ruby
#1
Another plea for help if I may.
As noted on previous posts I had the engine and gearbox out of Ruby to have the block professionally re-honed, check the pistons which were all ok but new rings fitted by the honing man.
I did not disturb the bottom end or the main bearings 
I have returned the engine and gearbox back in one piece and boxed everything back together and apart from a leak from the bolts on the side water jacket all seems good.

On starting, she fired up first time, unfortunately this was followed immediately by a high pitched squeal and so I shut her down instantly.
Turning the engine over by hand you can hear the pistons move up and down in the bores as the new rings on the pistons slide against the honed surface, which "to me" quite rough, but in ignorance this may be as it should be??
I have since tried again with the same result each time, I have pumped the clutch pedal and this makes no difference, have ensured oil is in the clutch release race.
Any assistance would be much appreciated.
I attach a link to the a short video in which the noise is pretty evident
Cheers, desperate of Rainham!!   

https://youtube.com/shorts/ATZRtPZPU1k?feature=share
Reply
#2
Can you see any marks on the rear face of the flywheel?
Reply
#3
I hope the rings have been gapped correctly, if they are too tight that could create a sound like that...
Reply
#4
Hi Denis

Following on from Ruairidh’s question have you replaced the flywheel cover?  If so try running the engine without it.  I had just this problem with my first special, sounded like a wailing banshee. Adjusting the cover solved the problem.

Cheers

Howard
Reply
#5
Ruairidh, I have checked again after your comment, but prior to fitting the gearbox on the bench I had checked all was "clear" and again after the gearbox fitted. Turning the engine over by hand there were no issues noted.

Ivor, I have to say I am in the dark here. The block, head and pistons with the original rings were handed over each pitons clearly marked to its relevant bore. It was the recommendation of the professional to change the rings and whilst I cannot remember the exact conversation we had when I collected the block etc I believed they had been checked for correct gapping.......??
The new rings are not the same as those I had originally fitted the second ring (middle) is made up of two thin flat rings which are set with the gaps 180 degrees apart.

Howard, the flywheel cover is off as you can see in the video.

I have to say in my limited knowledge of rebuilding A7 engines ....or any other engines for that matter, my initial thoughts were that it has something to do with the rings or bores as these is the only things that have really been worked on.

Any other thoughts.....I really do not want to take it all out again
Reply
#6
It would be a good idea to go back to the person who bored the block and ask them if the rings were gapped, and what that was.
Reply
#7
Hi Denis

My first thought was that maybe the pistons and rings were lacking a little lubrication - they would normally be covered in oil from the last time of running, and would be re-covered by splash once the engine had run up for a bit, but with a fresh assembly could possibly be a bit dry initially ? A squirt of engine oil down the bores and a few turns on the starting handle with the plugs out would eliminate that cause.

However, the sound on the video is (to my ears) more like something rubbing on a part that is continuously rotating rather than the 'pulsed' sound you would get from pistons reciprocating in the bores. It's not an over-long starter motor bolt rubbing on the flywheel is it ?
Reply
#8
I agree with John, it sounds to be a constant rotational noise, hence my first suggestion to you Denis.
Reply
#9
John, having discussed this with bruvver Pete, we thought the same, dry bores. And so, exactly as you described, I put oil down the bores, left this overnight and worked it up and down on the handle, but with the same result when started her up.
I will not be able to get in the garage now for a few days now but will try checking the bolt on the starter motor, this was not fitted when the engine was out on the bench. It would be great if it is, I did go out and check after Ruairidh made his initial comment but could see no evidence of any fresh marking on the flywheel.
I will let you know
Thanks folks
Reply
#10
Dennis
Sorry to hear about all the troubles!
Having carefully read and listened I had exactly the same problem now years ago.
My problem was one of the rear sump bolts was when fully tightened just long enough to catch the flywheel.
Sorry if you already checked this !
Good luck with resolving the issue.
Regards
Tim
Reply


Forum Jump:


Users browsing this thread: 2 Guest(s)