1962 Arrow Starting Problems

[White.John.A]

Hi all,
Yes I'm still wrestling with the running of the bike.
Can anyone help me solve the problem I’m having with my bike. It does between 5 to 13 miles before it suddenly stops. The following day it starts quite easily. Between 1 and 20 kicks, and runs quite nicely in the garage. I have now stripped it down again to have a look at the seals, because when I took a pressure and vacuum test reading they were very low and very inconsistent. I.e. 40 psi near side and 60 psi far side and varying. At the end of last year, the readings were 130 psi in both cylinders. This reading was taken just after a rebore. Can any body tell me what the expected cylinder pressure should be? With my limited knowledge the seals appear to be O. K. I have sent off for some new ones, which I intend to fit when they arrive. Having stripped it all down, I can see in the centre of the casing, an oil hole. It comes from the top of the casing on the near side, to the centre lip that separates the bearing from the seals between the two fly wheels. On the far side there is a horizontal hole that goes from the bottom of this oil way to the near side. Is this how it should be? The reason being, I think this would allow each cylinder to loose compression in the sump. Also I can’t see how the outside second oil seal would get any of the oil from this hole. Does this matter? As the oil is in the petrol, and so all bearings and seals are lubricated when the bike is running, which seems to make this oil way redundant?
In trying to trace the problem with lack of compression, I have pressurised the sump and used soapy water around the joints. I have also tried a smoke test. Nothing showed up with either test. When taking the cylinder heads off, the near side cylinder head gasket appeared to have been leaking slightly. I had originally torqued up the heads using the 18 Ft. Lbs reading I found on this sight. This appears to be very low to me, as my torque wrench starts at 20 Ft. Lbs. I then tightened up the heads to 30 Ft. Lbs and used Wellseal on the gasket to try and make doubly sure that the heads were not leaking. Before stripping it down I tightened down the heads by hand and checking the result with the torque wrench. This was 40 Ft. Lbs. The heads were machined flat at the time of the rebore, and they do appear to be O.K. now.
Finally. When the bike stops, it appears to me to have run out of petrol? There is plenty in the tank, and the little hole in the petrol cap is nice and clear, and I have made sure that the seat does not block it. I have now purchased another carburettor off EBay, and have used this one to compare. This made no difference.
In the strip down I have removed the exhaust pipes and stood them vertically in the corner of the garage, there is now quite a large black puddle of petrol/oil under them. Would this be quite normal as the bike is not working properly?
Any help or suggestions for me to try would be much appreciated.
John

[bh.sprint]

Hello John,

I've just checked an engine casting and there is a hole which collects oil from the near-side cylinder ( at the bottom of the transfer port ) and comes out into the spaced between the centre bearing and double oil seal. The drilled hole does just break into the centre bearing recess but will be blocked by the bearing when it is fitted.

Does the engine give a good spark when/after it has stopped ?

Brian H.

[White.John.A]

Hi Brian,
Thank you for checking the oil way for me. I’m not sure why the horizontal is there. Now you have confirmed that that’s the way it is, I will not concern myself with it.
The spark has been an issue for me. As it has been quite inconsistent. Through the winter I have put new plugs in, rehired the ignition system and fitted ignition switch. Also replaced HT leads, and wired them direct to the plugs without the suppressor caps. At each stage I have road tested the bike. It would run quite nicely for a while, and just as I was thinking I had solved the problem, it would slowly come to a holt. And I would push it home again. While on the test runs it did on some occasions go slower when I opened the throttle and sometimes would work normally. During the winter I got talking to a bloke who has refurbished a few bikes. He came to my house and spent a couple of hours on the bike and got it going nicely. That afternoon I thought I would do a test run, and the bike wouldn’t,start. The next day it started well and ran normally in the garage but broke down on the test run.
John

[Trevorc]

Hi John, I had a very similar experience with my Leader. The problem for me was solved by replacing both the condensers. A cheap fix if it works.

[White.John.A]

Hi Trevor,
I have read various articles on condensers. One said “I have worked on bikes for thirty years and never had to change them .” The other one said “ he has had new ones letting him down.” I decided like you, that it was an easy and cheap thing to change. So they are both new. I have actually thought about putting the old ones back. To see if the new ones are faulty.

[bh.sprint]

Hello John,,
To answer your question from the first message. The compression pressure is normally well over 100 psi for the Leader/Arrow engine and after a rebore it will be less until the rings bed in properly.

Is the fuel getting through to the carb, the reason I ask is because I've just repaired a tap for an Arrow and it was blocked wth fine sticky silt all around the filter. The blockage needed drilling out to remove it , especially the reserve hole and the filter then needed replacing.

Hope you eventually find the cause of the problem.

Brian H.

[White.John.A]

Hello Brian,
Thank you once again for the information. Due to my inexperience I am never quite sure when things have deviated from the norm. I have taken pressure readings quite regularly, and each time they are different. The reading after the reborn was 130 psi in each cylinder. So when it dropped to 30 I thought there was a serious internal problem. Originally the sump pressure and vacuum was holding evan though I was still having this problem when on the road. Just before I stripped the engine down the pressure vacuum was not holding. So something had changed. With the bike stripped down I can’t see anything wrong.
The petrol tap is new and there has never been any sediment on the filter.
I sometimes think I should be looking for something small but odd rather than something major. I have been looking out on this site for members who have had unusual things wrong. But to date nothing fits my problem.

[Roger James]

Picking up on your first message, first line regarding travelling 5 - 13 miles before the engine suddenly stops. As silly as it may sound many an Arrow, including my own has been running fine after setting off on a journey only for the engine to faulter and stop but would re start not long after and would be able to resume the journey for the engine to stop again a few miles down the road, it turned out to be the base of the seat, with my weight upon it sealing off the air vent hole in the top of the petrol filler cap causing a vacuum within the tank after a few miles, check that the air vent hole is clear, there should be a small ball bearing in the bottom but sometimes these have been removed by owners, note the position of where the vent hole is and reposition it to hopefully avoid it getting blocked. Not too sure what to think about the compression readings you have been getting but want to say, I always thought the readings depended on how well the piston rings were sealing on the bore rather than anything to do with the seals, and checked dry and wet, I coould be wrong on that one so will leave it to those with more knowledge on the subject. Jess

[White.John.A]

Hello Roger,
At the moment everything is worth looking into. The air way in the Petrol cap has the ball bearing in tact. What I decided to do was to drill a small horizontal hole connecting with the existing vertical hole. The idea was that should the seat come down on the Petrol cap air could still get down to the tank.
As far as the cylinder pressure is concerned, I think you are right. I just don’t know at what reading l need to look into the situation. Because I had such a low pressure reading I thought the rings might be broken.

[melvyndstimson]

Hi
Just been reading your starting problems ,I appear to have its brother in my garage .Its had a rebore ,recon crank, new Viton seals all round and

went quite good up till last week , Then it started when it felt like it and then nothing .Mine has good spark and petrol , all good connections .

I appear only to have about 50psi ish on each cyl, I'm thinking its coming apart ,Seals perhaps !!! Good luck with yours .

Melvyn Stimson