gritineye Posted October 16, 2011 Share Posted October 16, 2011 AS always, inspired thinking...can't hurt to try it, as you don't tow anything heavy and are not blessed with too much power it should be OK.......maybe :undecided: Quote Link to comment Share on other sites More sharing options...
rbrtcrowther Posted October 16, 2011 Author Share Posted October 16, 2011 It'll be just fine if i can pull it off. It only need to a dribble to keep the bearings wet. I just need to figure out some oil scoop fittings. Has anybody got any pictures of the oil jet holes with the pinion removed?..... Quote Link to comment Share on other sites More sharing options...
cosrec Posted October 16, 2011 Share Posted October 16, 2011 I like your approach i am a great believer in simple is good and best. I dont know the lay out so cant comment but after reading back through this post a lot of theses vehicles will have been riding about for many years with broken pumps and come to no real harm. So anything you can do to supply oil is a bonus. Quote Link to comment Share on other sites More sharing options...
rbrtcrowther Posted October 16, 2011 Author Share Posted October 16, 2011 cheers for that i don't know why i went down the complicated pump route in the first place. Found a piccy of the oil jet holes Looks like i might have to drill one or both of them out to get a decent size scoopy thing in there. I'll try one first and see how much gushes out. There's nothing better than sitting under a Scammell explorer on jacks with the whole thing whirring away in top gear thinking "if this falls off now" or "wow......that propshaft is rather scary..." Point also given to anybody who can spot the inside of their Scammell back axle in the picture.. Quote Link to comment Share on other sites More sharing options...
gritineye Posted October 16, 2011 Share Posted October 16, 2011 Looking at how the paint is worn off by the oil holes it looks like a fair bit of oil flies straight back off the worm anyway. Quote Link to comment Share on other sites More sharing options...
julezee001 Posted October 20, 2011 Share Posted October 20, 2011 Point also given to anybody who can spot the inside of their Scammell back axle in the picture.. That's Simons rear axle, posted what seems like, and was years ago! Lots of backlash on worm gear, partially caused by the slightly worn main bearing (the really expensive one!), but mostly by the worn aluminium casing that should clamp the bearing and shims. The pump shaft was broken, so no oil flow at all. I fitted a spare pump, which eventually span up and pumped using an electric drill, and a spare housing. I've not looked in there since, and I've not looked in mine yet. I suspect my pump works as it seems to seep oil from the unions on the heat exchanger. Another couple of items on the "Things I Ought to Do List". I'm fairly convinced the only need for the pump is to circulate the oil through the heat exchanger. I would think it's only important when towing large loads making the axle oil work hard. The holes are so small from the pump into the casing, that they can't be important for lubrication compared to the oil shifted by the crown wheel spinning. More likely they spray a certain amount of cooled oil onto the worm gear to help keep it cool, and to tranfer heat away from it? Jules Quote Link to comment Share on other sites More sharing options...
gritineye Posted October 20, 2011 Share Posted October 20, 2011 I'm fairly convinced the only need for the pump is to circulate the oil through the heat exchanger. I would think it's only important when towing large loads making the axle oil work hard. The holes are so small from the pump into the casing, that they can't be important for lubrication compared to the oil shifted by the crown wheel spinning. More likely they spray a certain amount of cooled oil onto the worm gear to help keep it cool, and to tranfer heat away from it? Jules Makes sense Jules, an opinion shared by quite a few Explorer owners who have run for years without a pump. Quote Link to comment Share on other sites More sharing options...
cosrec Posted October 20, 2011 Share Posted October 20, 2011 Just spent a little time trying to work out where the oil is getting thrown about as vehicle is travelling seems to me crown wheel is pckinging it up out of bottom of diff and throwing at front bearing. In turn worm is screwing it back towards back bearing dont know done my head head in trying to work it out. but if this is the case the pump is only there for extreme conditions at slow speeds Quote Link to comment Share on other sites More sharing options...
gritineye Posted October 20, 2011 Share Posted October 20, 2011 Does it help your head to remember Scammell prop spins the opposite way to most? Quote Link to comment Share on other sites More sharing options...
rbrtcrowther Posted October 23, 2011 Author Share Posted October 23, 2011 Just spent a little time trying to work out where the oil is getting thrown about as vehicle is travelling seems to me crown wheel is pckinging it up out of bottom of diff and throwing at front bearing. In turn worm is screwing it back towards back bearing dont know done my head head in trying to work it out. but if this is the case the pump is only there for extreme conditions at slow speeds Yep lots of oil scooped up by the crown wheel rotating forward onto the worm where i'm pretty sure it most is flung off and some is screwed forwards (with the worm and the top of the crown wheel and then it makes it's way to the front of the worm shaft and the front bearing. Now the rear worm bearing is having most of the oil screwed away from it. There is also a shoulder that the bearing sits against. I'm pretty sure some oil will find it's was to the rear bearing as it has to be able to find its way through from the other side when the pump is fitted. the Scammell Pioneer never had an oil pump or cooler fittted however a sort of Scoop was fitted near the crown wheel to divert oil to the rear worm bearing. This scoop was deleted on the explorer, Instead a 1/8 hole was drilled in the body of the oil pump to alow oil out into the rear case to lubricate the pump gears and also the rear worm bearings. (if anybody can spin their pump up and see if this oil hole has bunged up it would prove that the bearing can run with no supply from the pump) I am only trying to get a bit more oil to the rear bearing just for piece of mind. I'll let you know how i get on... Quote Link to comment Share on other sites More sharing options...
rbrtcrowther Posted October 30, 2011 Author Share Posted October 30, 2011 Hole drilled and tapped to half inch BSP Scoop made and screwed in went dark bloody poxy winter time. Will they stop debating it and just put the bloomin clocks another hour forward in summer, god i'd rather have light in the evening and get up in the dark..... Anyway after drilling the hole i shunted the Scammell back and forth in the low gears (only about 10 foot due to lack of space) and not a sausage came out the hole. Had a look through the hole and could see oil on the worm part of the shaft but nothing towards the back bearing area. next step is to sort the fittings to the rear case then jack it up and run it at different speeds and gears now the scoop is fitted to check the flow of oil. Quote Link to comment Share on other sites More sharing options...
rbrtcrowther Posted October 30, 2011 Author Share Posted October 30, 2011 Just been looking back through my blog and noticed something that might be of interest that i missed before. This is a picture of the broken and devastated oil pump and gears i found in my rear axle. Now it had clearly been broken for a very long time before i got it and i drove it 7 miles home along some quiet back lanes to get it home. It then sat for a couple of years while i sorted the cab and then it had a couple of very short runs down the drive as a test. Then i thought i would check the axle oil pump and found this.........But what i overlooked was the oil in the rear case....It's clearly in there so oil must get through the rear bearing even at low speed.....Interesting......all the bearings seem fine, i think it must have run for years without a working pump possibly doing some heavy towing.... What do you think? Quote Link to comment Share on other sites More sharing options...
rbrtcrowther Posted October 30, 2011 Author Share Posted October 30, 2011 On another note as the Scammell was named after my ex girlfriend there has been much debate over the renaming of the old girl Especially as i am now married to my wonderful Wife Paula. Anyway having to keep this blog going with the name of my ex on it is slightly annoying and results in a certain amount of Frowning from my wife bless her, So there will be no more posts on this blog, It's time to move on. I shall continue my seemingly endless restoration blog in a new thread.....I'll see you on that....:wave: Quote Link to comment Share on other sites More sharing options...
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