The Honda Owners Club

Hi all,

I have a bit of a problem with Iggy, it's not a major issue as I hardly ever ride in the rain (I don't find it enjoyable) but it would be handy to have the problem sorted in case we're out and get caught in rain.

My Dad emailed me this...

I have replaced the spark plugs (several times), the spark plug caps have been replaced once, the ignition coils and HT leads are the origial items. The problem is that the engine misfires in the rain (runs on 1 cylinder), I don't know which cylinder cuts out though, it only happens in the driving rain. I have tried waterproofing the leads and coils with silicone spray, but it doesn't last long, it only masks the real problem. The bike did work fine for several years, I rode it work at Oxford often in downpours without any problems at all. I suspect the HT leads have deteriorated with age and are the problem, but I don't know if they can be replaced seperately from the coils.

How big a job is this, replacing HT leads & coils? And is it expensive to fix?

Thx

Lindz

Hi Lindz,

CX500 problem in the rain: This is a common problem with old CX's and there are several things that could be the cause.

So let's start at the front and work to the back.

The first thing to check:

At the bottom of the Cylinder heads where the sparkplugs sit (on the outside) are drainage holes if these get blocked you may find that water is accumulating around the spark plugs causing a short circuit .... clean these out .... don't remove the plugs to do this or you may get dirt falling into the cylinder. I use a cleaning brush for a recorder to do this (obtainable from a music shop) this is perfect for the job.

Second:

Check that the rubber seals that sit in the top of the spark plug holes are sitting correctly and are in good condition ... push them into the holes a little to try and get the seal as good as possible.

Third:

HT leads can be replaced without replacing the coils and reasonable expense, these could be the problem but knowing the CX500 prblem I believe that the problem lies elsewhere. I have had this problem myself and bought a second pair of coils complete with leads and plug caps off ebay at a reasonable price (spares of this ort never go amiss) I think I paid around 15 quid for the pair.

Forth:

Check the connections on the wires that go from the coils to the CDI Unit for any signs of corrosion. Clean and spray with WD40 or silicone spray.

Fith:

Check the connections under the seat that go from the CDI to the Alternator/Generator first dirt clean if required.

Sixth:

This is where the problem sits more often than not....The cables that go into the rear of the crankcase to the Generator/Alternator the rubber grommet that sits around the cable is often perished,: this can be sealed using heat resistant black silicone obtainable from most Motorists discount shops (replacing the grommet alone is impossible as it is part of the Generator.

Seventh:

The seal on the cover to the spark plug advancer is perished (also one of the most likely places for the fault to sit) The cover is a pig to get at without removing the engine...but it is not impossible (removing the water expansion bottle may make this easier) Obtaining a new seal for this cover may cause problems as David Silver does not have one in their list, although they may possibly be able to get one so email them. However the cover can be quite easily sealed using the same black silicone sealant as in point six.

One or more of these points are probably the cause of your problem !!!

Regards Witch

Thx Witch! I'll get on with that list and let you know how it goes.

You're welcome Lindz

You don't have to wait for the next time it rains to see if you have cured the problem, just get the garden hose out (on spray) and give it a good dowsing with the engine running....sounds brutal I know but if it runs well under such conditions you know that it's fixed

Run the engine in the garage in the dark and you can sometimes see high tension sparks leaking away from the HT leads to earth on the frame.

You could also spray some water onto the leads with a small garden sprayer whilst the engine is running. This will show if the leads are leaking.

Don't forget to open the garage door a little so you don't suffocate!

Great Tip Dave,

However having had the same problem myself with a CX500 I visited the CX and Gl owners club forum, and as it seams that this is a common problem with CX's. Around 9 out of 10 times it was the seal on the spark advancer cover plate at the rear of the engine or the grommet round the generator cables going into the rear crankcase.
As this may be the 1 out of 10 in this case I have suggested a thorough check from front to rear and your tip will definately make it easier to rule out HT lead probs (or to detect them) My problem was definately one of the 9 out of ten

Hi Lindz,

David Silver has a gasket for the rear cover plate it is called a Generator Pulser Cover Gasket
http://www.davidsilverspares.co.uk/part ... art_40236/

Regards Witch

I just love how when you have a problem there are good folks out there who can offer a range of solutions and suggestions

Looking forward to finding out if you got it fixed Lindz

Shellshine wrote:I just love how when you have a problem there are good folks out there who can offer a range of solutions and suggestions

Looking forward to finding out if you got it fixed Lindz

Yep I agree Its great how everyone on here offers help and support on here, I think this is the friendliest forum I've ever been on!! I can't wait to have a go tinkering with Iggy and hopefully fixing the problem.

Witch - Do you know how to remove/fit new HT leads at the ignition coils?

My Dad emailed me the following...

The plug caps simply screw into the other end easily, but I don't if the ht leads are secured into the coils in the same way. I do suspect that it is the ht leads that are the problem, as when I took the trouble to spray the leads with silicone waterproof spray and then wrap the coils in plastic bags to keep out the water I didn't have any cutting out the last I rode the bike in the wet, which was last year sometime.

Thx

Lindz

Hi Lidz,

I think I may have just wrecked one of my spare coils removing the ht lead I won't know until I put it on the bike and try it which I can't do before next week monday or tuesday.

I was under the belief that the leads just pushed in so I pulled one out
The lead goes about 2 inches into the coil I pushed it back in but I may as I said have wrecked it and it is possible that the leads are not replaceable

There are now after market coils available for CX's I believe, I am sure I have seen them for sale somewhere but I can't remember where at present but I will do some searching.

The other possibility is second hand ones from Ebay

Cheers Witch

Hi Lindz,

Did you get your bike sorted?
Well I confirmed my fears .... I have recked a perfectly good coil by pulling out the HT lead (I checked it just before stripping my CX for a complete restoration)

So, the HT Leads are not replaceable on CX500 coils only the whole coil including leads

Regards Witch

It is possible to cut the leads back and fit a splice with a replacement lead, or at least you ues to be able to!

Nope not got it sorted yet. Jacks bike is still in bits so all the spare time fixing bikes is going on that at the mo, soon as that is on the road I'll get Iggys problem sorted... Its not too major for me at the mo cos I don't like riding in the rain so another few weeks won't make any difference. I'll let you know how it goes though