Hymac 690

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Jeremy Rowland
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Re: Hymac 690

Post #131 by Jeremy Rowland » Fri Jun 06, 2025 7:29 pm

Well you can arrange anything except the weather and as I had already booked Thursday off work I was determined to get up there and see if I could get anything done, on the plus side my inlet manifold has been repaired, so I thoroughly cleaned it off and gave it a coat of paint just to tidy it up, must say that Lee has made a fantastic job of the repair too :claphands: . I forgot to take any photos of the finished article.

Jeremy




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Topic author
Jeremy Rowland
Moderator
Posts: 8866
Joined: Sun Aug 05, 2007 8:36 pm
Real name: Jeremy Rowland
Has thanked: 1995 times
Been thanked: 1793 times

Re: Hymac 690

Post #132 by Jeremy Rowland » Sat Jun 14, 2025 12:12 am

Well I suppose that it's true for many different restoration jobs as you do one job, it automatically leads straight to the next one; now I had to drain the hydraulic oil because I needed to jack the engine up to get the sump off for the strip down and to do that I had to disconnect the main hydraulic hoses to the pump.
This was not a particular issue to me as I wanted to change the hydraulic oil anyway, however while the oil was dropped out it goes without saying that the hydraulic oil filter would also be changed, it is housed on top of the main machine body beneath a round steel cover some 340mm in diameter. The issue was that four of the cover bolts snapped off when I removed the cover. These were originally studs which had been welded into place as part of the hydraulic tank assembly, I wasn't quite sure how I would repair them but decided to drill them through, re-tap a new thread and screw a bolt in from underneath, the issue was preventing and swarf debris from entering the tank, this was done using some wood to cover the filter hole, plenty of rag and a very powerful magnet. The repair was a success so that was another job done out of the way. :thumbup:

Jeremy


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