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Discussion Starter · #1 ·
Hi All.

This is my first post on the new forum and I have a problem and need help.

I have finally finished rebuilding the engine in my early CX500 Shadow.

The engine was completely pulled apart to every nut and bolt and its had new rings, bearings,and bores were honed, new valve seats cut etc etc.

I adjusted the valves this afternoon and then spun the engine over a few times without the spark plugs fitted, expecting the red oil pressure light to go out. But it didn't ???? I was trying to be very cautious and was only giving the starter button short 3 - 5 second bursts.

I removed one of the valve covers and there is definately no oil getting to the rockers or top of the engine.

In total I probably only spun the engine for about 20 seconds. Am I being too cautious and didn't give it long enough or was I right in stopping ??

I have checked the connection where the wire joins the oil pressure switch just in case I had forgotten to tighten the screw but it was ok.



Any advice anyone can give me on what I should check or what my next step should be would be greatly appreciated as I do not want to damage my new engine.

Thank you in advance

Oldlonely...
 

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When starting a fresh engine rebuild this is my procedure.



Pour copious amounts of clean engine oil over the valve train and make sure it drips down over into the engine then put the Head covers back on.



I assume you followed correct procedures including coating big-end shells with molypaste or at least lots of clean engine oil?



Also I assume you fitted all oil orifices and dowels correctly.



When ready to start the engine I start and hold the engine at around 3,000 rpm for say 20 seconds to allow the oil pump to quickly get the oil around the engine and NOT let the engine idle.Unfortunately your over caution will will mean now the engine has received a little more wear than it should as this initial engine start procedure is important to a good build but with luck not by much.





I would have preferred you had been in contact with some one like myself whilst you did a major job as we could have varfied all procedures as we went along.I have re-built several of these engines with a higher level of success each time and my present main engine has over 18,000 miles on it since a crank change,new shells,new valve guides and valves and my 2nd CX has around 8,000 miles similar.





Also this is the running in procedure I used on both engines with new rings,





http://www.mototuneusa.com/break_in_secrets.htm



I then ride the engine for around 100 miles and then replace the oil and filter to allow for any metal debris that may have been honed off from the new rings and re-check the head bolt torques which I also check after one heat cycle of bleeding the cooling system when cold,



http://www.pdsrecording.site90.com/cxgl500/Coolant.htm
 

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oldlonely.while im not going into what shep has already said.



i seem to remember from the old forum......under the cylinder heads are oil valves with an o-ring[1 per head]if you fitted these upside down,which is easy to do,it would restrict oil from reaching the top.

just a thought
 

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oldlonely.while im not going into what shep has already said.



i seem to remember from the old forum......under the cylinder heads are oil valves with an o-ring[1 per head]if you fitted these upside down,which is easy to do,it would restrict oil from reaching the top.

just a thought


These are called,"Oil Orifice" in our engines Bandit as per above.Yes you are right if any of these(One each in the heads and one in the front engine) have been reversed they will cause problems/premature wear.




http://www.cmsnl.com/honda-cx500a-1980england_model16465/partslist/E18.html



however I think the PO may just not have revved the engine enough to get pressure up.
 

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Oldlonely

when I saw the headline I thought you'd run the motor !!!

so glad you didnt and are exercising due caution before

firing her up.



Firt check whip off the oil pressure sender and spin the motor until

you get oil coming out the hole

If you dont get any in say 20-30 seconds I'd take the front cover off

and examine the innards again

using a car/van battery as a booster can help here

spinning it on the starter with plugs out isnt putting much load on any major

bearinsg so yer in fairly safe waters

(I assume you lubed the beaings on assembly)

If you get oil coming out then a pressure gauge is ideal next but failing that

do it again with your finger or something to allow the pressure

to build and act against and see if it squirts past yer finger



If so refit the sender, connect it up and spin again watching the light

With a good battery you should get the light go out in say 30 seconds

the first time and much sooner after its been primed



If you dont theres a problem

previous arrors I've heard over the years have been



Inside front cover

The small but VITAL O rings in the front cover lost or omitted

the small alloy metering jet lost or omitted

Pressure releif valve stuck open

assmbly error on pump/chain

blocked strainer



Heads

If the O rings or metering valves on the head have been omitted you should stil get flow, but it would compromise pressure as the idea is to lube the rockers etc but keep high pressure at the major bearings



I dont thnk I need to tell you this as I reckon you know but

All you have at the Mo is a problem, trying to start it without knowing

you'll have full oil pressure could turn it into a disaster.



Good luck let us know what you find
 

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Oldlonely









I dont thnk I need to tell you this as I reckon you know but

All you have at the Mo is a problem, trying to start it without knowing

you'll have full oil pressure could turn it into a disaster.



Good luck let us know what you find


Good point Reg.Best err on the side of caution.
 

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Hi All.

spun the engine over a few times without the spark plugs fitted, expecting the red oil pressure light to go out. But it didn't ???? I was trying to be very cautious and was only giving the starter button short 3 - 5 second bursts.

I removed one of the valve covers and there is definately no oil getting to the rockers or top of the engine.

In total I probably only spun the engine for about 20 seconds. Am I being too cautious and didn't give it long enough or was I right in stopping ??


Have a look at this video.

The oil light goes out after about 12 seconds of continuous cranking (you can see the glow from the temporary oil light up by the pushrods), and oil only reaches the rocker shafts quite a while after that:





[media]http://www.youtube.com/watch?v=-6OeMW2K8bU[/media]
 

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when I rebuilt my engine, it took longer than 20 seconds to get the oil pressure light to go out, plus the fact that the little screw that holds the switch in place was loose, it might take longer.



As long as you don't actually start the engine with the plugs in and running, then just cranking over on the starter to get the pressure up shouldn't do any harm...



One thing to do is when filling up with oil, pour it in over the rockers, instead of the oil filler hole, that'll help distribute it.



I reckon another 10-20 seconds and you'll get the light to go out. next time it'll be a lot quicker as it's already primed.
 

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Shep,



I agree with yours and Motomans procedure on breaking in and engine. What is your opinion of his intake porting which is shown down toward the bottom of his site? BillRod
 

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Shep,



I agree with yours and Motomans procedure on breaking in and engine. What is your opinion of his intake porting which is shown down toward the bottom of his site? BillRod


Bit like some other threads.You will get those who says it works well and those who incorrectly think that having a rough casting surface aids the atomization of the fuel.According to one of my M8s,who Drag races GSXRs,you want a smooth intakes polished to aid in the fast flow of the fuel into the engine and polished exhausts to help the engine scavenge the exhaust fumes out.The atomization should be taken care of by the carbs/Injection system.



AFAIK all race engines have polished inlet and exhaust ports which speaks for itself IMHO.The only reason I can see for the rough castings in some engines was most likely to keep mass production costs down.I always clean and semi-polish my inlet and exhaust ports when I'm doing head work.Can't say it's improved anything as I have nothing to compare it with but it's done no harm and with both my CXs having electric fans they are quite peppy anyway
 

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Discussion Starter · #11 ·
Hi Guys,

Thank you for all of your replies.

This has been my first full engine rebuild and has been about a year in the process as I am a sales rep and am away from home alot.

(I have also painted the engine and fully polished the front and rear engine covers which took a long time)..

It has also taken a long time as I am pretty anal about things. I posted many times on the old forum asking lots of questions when I wasn't sure about something and used Sheps advice and same method for torquing down the cylinder heads.I know for sure that I have not left out any dowels or o rings and I know that I have the little oil jets under the head fitted the right way round because I looked at another engine I have here.

When I assembled the engine i did use engine assembly lube and lots of engine oil.

Shep, when you say start and hold the engine at 3000rpm, do you mean actually try and start the engine with the plugs in and leads fitted ?

My train of thought was that I needed to get the oil circulating around the engine and get the pressure up without putting too much load on the engine so I was just spining the engine on the starter with the spark plugs out, and as I said I only did this in short bursts for about 20 seconds in total. As the light didnt go out immediately as I thought it would, I stopped and then got on here to ask some expert advice before I screwed anything up. I didnt know how long it would take for the oil to pump up around the engine. Maybe I didn't do it for long enough ?



OK, where do I go from here. I will take the valve covers back off today and pour some engine oil over the rockers and let it run down into the engine from the top. I will also remove the pressure switch and make sure it is ok and oil squirts out.

I will also take Reg's advice and connect up my boat battery with jumper leads so the engine spins alot faster.

I will again do it with the spark plugs not fitted to lessen the load on the engine, and only maybe give it 20 or 30 seconds max.

Will post back what I find.

Thank you for all of the advice so far.

Oldlonely..
 

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Oldlonely

I dont see the point of pouring oil down the rockers

It wont go anywhere useful in terms of where the oil gets pumped

under pressure and may prevent you seeing the oil that does get pumped

seeping out of the rockers.

Hopefully your just being a wee bit over cautious and thats not a bad thing

I'd just do the sender out, watch for oil then if you see it pumping, sender in and a 30 second

crank while watching the oil light.

If/when it goes out, leave it a few minutes to let the starter cool and pressure drop then

a quick crank should see the oil light go out immediately

( If you want to be to be very very sure leave it for an hour and do it again)

IF it does I reckon yer good to go.

If it doesnt you need to investigate why
 

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I differ from Reg and have always poured some oil over the Rockers and valves just to pre-lube them.It has done no harm to my engine builds.



Yes I start the engine with the plugs in and hold at 3,000 rpm as per above.If you have followed the advice in the manual and know your work then there should be no problems.
 

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Was your oil pump installed dry? Im not sure on these little engines, but the large diesel engines I build at work dont like to build pressure unless you prelube the pump before installation. This helps seal the pump and pick up oil immediately. I usually prelube my oil pumps with Lubriplate, just fill it up with it, works great. But you dont want to use regular white lithium grease because it doesnt break down like the Lubriplate and can actually plug up oil filters.
 

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Discussion Starter · #15 ·
Hi guys, well I took all of your advice but didn't get the outcome I was hoping for.

I did remove the valve covers and pour a small amount of oil over the rockers pushrods etc to make sure they were well lubricated.

I then refitted the valve covers and removed the oil pressure switch and was a bit concerned when I looked at the end that is inside the engine when it is screwed inplace, to find that it was dry !! (I was expecting it to be wet with engine oil).

I hooked up the boat battery with jumper leads so it would spin faster and cranked it over (plugs out).

I did not crank it for very long but no oil came out of the oil pressure switch hole and I could not even feel any pressure there when I put my finger over the hole while it was cranking..

I must say that after well over a year of rebuilding, what I thought was going to be a very happy moment, (finally getting to start my bike), has turned out to be a bit of a bummer. Am very disappointed in myself.

Its saturday here so I guess todays job is going to be removing the radiator, draining the engine oil and removing the front engine cover and maybe the oil pump, to see what I can find.



Thank you for all of your interest and assistance so far.

Oldlonely.
 

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bummer! only thing i can imagine is the oil pump is fubar. if you drain the engine and turn it over by hand on the front, you usually hear slurping sounds as the pump sucks up the oil through its gauze. if you don't hear that I guess it's faulty, or somewhere along the way (o-rings etc) there is a seal failure.



I'm sure you'll get it running in no time though, just persevere and stay positive.
 

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Well at least its still a problem, a snag and not a disaster

had you run it.....................


I recall a guy on the old UK MSN forum who wasnt so cautious

and ruined his motor due to omitting some of those small but

vital parts.

Ouch!!



I still dont see any point in pouring oil over the rockers

you want the stuff inside between bearing surfaces

but thats just me I guess.

Oil bearings on assembly by all means



Chin up oldlonely ,you'll get there.

Just think how sick you'd feel if you hadnt been so cautious
 

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It's almost impossible for that type of oil pump to NOT pump oil if the pump is actually rotating. My guess is that your pump rotors are not turning or the relief valve is stuck wide open. There is a pin that holds the inner pump rotor to the pump shaft. If this pin is sheared or missing the pump would not rotate. I would also check the relief valve. If it was somehow stuck in the wide open position it might let all the oil escape the pump without building up pressure. I believe that it's the relief valve that actually regulates the oil pressure when it's working right.
 

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I still dont see any point in pouring oil over the rockers

you want the stuff inside between bearing surfaces

but thats just me I guess.

Oil bearings on assembly by all means


I did mine originally, because even though I'd already oiled everything during re-assemby, I thought it cant hurt to get some more oil over the pushrods, rockers, cam lobes, followers, down the drain holes, etc.



I also thought (probably wrongly) that it might help reverse fill the oil pump.



The last but best (lazy) reason I found was that while the engine was on the bench with rocker covers off, it was easier to just pour oil in the top rather than mess around with a funnel on the drain hole. When I bumped the starter for a bit, I would be able to see oil starting to flow to the rockers.



So basically it's not needed as long as you've lubed everything on assembly and I didn't bother doing it tonight when I filled my re-re-built engine up with oil, couldn't be bothered removing the rocker covers.
 
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