Quickfarms Posted May 14, 2019 Author Share Posted May 14, 2019 I woke the truck up today to move it from the dirt storage area to the asphalt so I can finally deal with the lift pump and fuel lines.Last weekend I decreased the injector pump and surrounding area with two cans of gunk engine cleaner and a bunch of waterToday I refilled the fuel filters, the primary was down a couple of inches.The truck started without much issue The new problem is the air pressure built up until the pressure release vented.Do I also need to replace the governor or is there another issue? Quote Link to comment https://www.bigmacktrucks.com/topic/54779-1985-rs688lst/page/3/#findComment-422738 Share on other sites More sharing options...
Brocky Posted May 14, 2019 Share Posted May 14, 2019 Probably the governor.. I have "rebuilt" them along side the road by pulling the plunger and cleaning with starting fluid!!! Be sure to take the small air line OFF First.. Ask me how I know!!! Quote Brocky Link to comment https://www.bigmacktrucks.com/topic/54779-1985-rs688lst/page/3/#findComment-422744 Share on other sites More sharing options...
Quickfarms Posted May 19, 2019 Author Share Posted May 19, 2019 Tuesday I removed the lift pump and fuel lines and dropped everything off at the parts house so they could make new fuel lines and get a replacement lift pump and I am in a holding pattern until they get everything. I did find a lot of oil crud on the block under the injector pump. It has a wet look to it just in front of the tach drive cable, which was very loose. It could be old crud mixed with the engine cleaner or a leak. I will wait until the engine is steam cleaned unless anyone has any other thoughts. Quote Link to comment https://www.bigmacktrucks.com/topic/54779-1985-rs688lst/page/3/#findComment-423127 Share on other sites More sharing options...
j hancock Posted May 20, 2019 Share Posted May 20, 2019 That would be my plan as well. Get everything clean and then locate the issue after a little run time. It can be tough to chase a problem that is coated in dirt. Quote JimIt doesn't cost anything to pay attention. Link to comment https://www.bigmacktrucks.com/topic/54779-1985-rs688lst/page/3/#findComment-423190 Share on other sites More sharing options...
Quickfarms Posted June 19, 2019 Author Share Posted June 19, 2019 I put the rebuilt lift pump in, along with new hoses and filters. After priming the truck ran good. That night it started right up after sitting for 5 hours.Today it was back to its old self in the morning but did start easily Now it has a new issue the fuel shut off lever will not move its full travel, it appears to be stuck in the run portion and won't rotate to the stop position. It moves about half of what it used to and the truck will not start So I am at a loss, what happened Quote Link to comment https://www.bigmacktrucks.com/topic/54779-1985-rs688lst/page/3/#findComment-425658 Share on other sites More sharing options...
j hancock Posted June 22, 2019 Share Posted June 22, 2019 I dunno? Take the cable off and see if the lever operates correctly by hand? 1 Quote JimIt doesn't cost anything to pay attention. Link to comment https://www.bigmacktrucks.com/topic/54779-1985-rs688lst/page/3/#findComment-425912 Share on other sites More sharing options...
Quickfarms Posted June 23, 2019 Author Share Posted June 23, 2019 In the run position it is a hard stopIt travels about 1", approximately half its original travel, towards the stop position and stops like it is bound up.If I crank the engine it may sometimes travel the full stroke but most of the time is limited to this partial travel Quote Link to comment https://www.bigmacktrucks.com/topic/54779-1985-rs688lst/page/3/#findComment-425958 Share on other sites More sharing options...
Quickfarms Posted July 18, 2019 Author Share Posted July 18, 2019 According to the local diesel pump rebuilder, the pump needs to be rebuilt.I have not found a mobile mechanic that is willing to work on a Mack engine but the pump shop will do the work.Since I am still waiting for the gaskets and some other parts I have been working on other projects. This is the frame before And this is it afterNow for the sad part, Monday I discovered that I needed a part for the Ford FT900. I emailed the old part number and vin to ford at 4 pm and by 10 the next morning I had the parts ordered, it will be here in 5 to 7 days, no shipping charges. Ford still supports these old trucks, to a point, but Volvo has hung Mack out to dry 1 Quote Link to comment https://www.bigmacktrucks.com/topic/54779-1985-rs688lst/page/3/#findComment-428181 Share on other sites More sharing options...
j hancock Posted July 18, 2019 Share Posted July 18, 2019 Fewer holes is always better. Quote JimIt doesn't cost anything to pay attention. Link to comment https://www.bigmacktrucks.com/topic/54779-1985-rs688lst/page/3/#findComment-428238 Share on other sites More sharing options...
Quickfarms Posted July 18, 2019 Author Share Posted July 18, 2019 Yes, it started with the new top hole being to close to an old hole Ford emailed me this morning that my parts are sitting in will call Quote Link to comment https://www.bigmacktrucks.com/topic/54779-1985-rs688lst/page/3/#findComment-428247 Share on other sites More sharing options...
j hancock Posted July 19, 2019 Share Posted July 19, 2019 Does seem that FoMoCo wants your business for a 30 year old truck. Hmmmm... Quote JimIt doesn't cost anything to pay attention. Link to comment https://www.bigmacktrucks.com/topic/54779-1985-rs688lst/page/3/#findComment-428292 Share on other sites More sharing options...
Patdbossct Posted March 7, 2020 Share Posted March 7, 2020 On 2/21/2019 at 10:12 PM, Quickfarms said: I was able to locate one new power window motor and it arrived today where did you find one? I'm looking for one too Quote Link to comment https://www.bigmacktrucks.com/topic/54779-1985-rs688lst/page/3/#findComment-444630 Share on other sites More sharing options...
Johnny cakes Posted April 16, 2022 Share Posted April 16, 2022 In the thread someone is looking for a power window motor. Did you ever find one? Do you have a part number on it? Quote Link to comment https://www.bigmacktrucks.com/topic/54779-1985-rs688lst/page/3/#findComment-495446 Share on other sites More sharing options...
Johnny cakes Posted April 17, 2022 Share Posted April 17, 2022 On 2/21/2019 at 10:12 PM, Quickfarms said: I was able to locate one new power window motor and it arrived today Where did you find one? Quote Link to comment https://www.bigmacktrucks.com/topic/54779-1985-rs688lst/page/3/#findComment-495508 Share on other sites More sharing options...
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