Honda Twins banner

1 - 20 of 22 Posts

·
Registered
Joined
·
19 Posts
Discussion Starter · #1 · (Edited)
I changed (or tried to change!) for the first time the oil on my 1985 450SC Nighthawk which I just acquired. I knew (as PO indicated) that it had a minor oil leak.
Based on the condition of the oil filter and the crud on the cap, looked like the PO had really not changed oil or the filter in a while. I cleaned the oil filter cover, the bolt etc with carb cleaner.
I removed the gasket and cleaned the seating there as best as I could. And based on the experience of folks here, I had bought a Wix filter with the o-ring and the gasket/seal/o-ring for the cover. I was careful not to over tighten the bolts. The oil filter bolt appeared somewhat difficult to tighten compared to the drain plug.

After I replacing it, when I started the bike, a steady stream of oil leaked from the oil filter. I tightened the oil filter cover some more - more than I assumed would be enough - I didn't use a torque wrench. The stream reduced but still getting a steady thin stream though it seemed to reduce after I cut the choke. and it was idling at around 1000 rpm. The oil pressure light stayed on - so I didn't run it too long.

The leak is entirely from the sides (gasket!) and not from the bolt (o-ring seems to be working fine there!). NO leak from the oil drain plug where I also replaced a crush washer.

I read on another site that some folks have had some issues with non-OEM gaskets such as the one on the Wix and some have fixed it by using a Honda OEM gasket which they claim is a little thicker. Is that an experience any of you have had? It did feel thinner than the one that I replaced.

Should I try changing the gasket with a Honda OEM one? Or do you think I should shop for a replacement oil filter cover on ebay. Any suggestions based on your experiences? Any help is appreciated!

Thanks in advance.
Sam
 

·
Registered
Joined
·
2,510 Posts
I've only used the oring on the oil filter housing
Are both surfaced clean and in good condition (no scrapes or damage to the surface)?
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #3 ·
I cleaned the surfaces of the oil filter cover inside and outside really well. But when I removed the O-ring on the cover, I noticed quite some deposits on the seat from the o-ring. So I scrubbed it as well as I could, and even used a pick to remove some stuff from it. but didn't want to scratch it so stopped after I removed most of it. There was some discoloration (probably baked from the gasket in that was quite resolutely unremovable with carb cleaner or wd-40 and a pick). Could that make such a difference?.

In fact, the leak was a steady stream. And I was maybe extra careful not to over tighten since I had read that the cover was aluminum and could crack if one did that. But I was shocked by the amount of oil that streamed/dripped out when the engine started up. It was significantly more than before I changed the oil and all the or-rings/gaskets.

Not quite sure what to try next. Try a different o-ring for the cover? Or a new oil filter cover?
 

·
Registered
Joined
·
2,510 Posts
The filter housing isn't symmetrical and fits into a groove tooth notch thing. Did you make sure it's lined up?

Edit: where is the leak from, top or bottom of the filter housing?
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #5 ·
I thought I aligned it properly with the two tabs in the groove but good suggestion - I will make sure it is aligned properly tomorrow morning.
Also the leak/stream is not from the bolt but from all the slides of the top of the housing. Which leads me to think your first question - has it been fitted properly may be the one to check first. The bolt was not as easy to screw in as I thought it might be.
I have one more question: after you push through the cover, then thw spring, then the washer, and then the filter, correct? Before you insert the bolt into the threads and tighten, correct?

But thanks, doode, maybe it is not seated completely properly.

Such an elementary thing, I assumed it must have seated properly if it was possible to tighten it and it looked correctly seated. But I will surely check this again tomorrow.
 

·
Registered
Joined
·
2,510 Posts
You might have cross threaded the bolt? Shouldn't be difficult to turn. Something to check as well.
As for assembly order, I can't recall to be honest. I'll head out in a bit and see.

Edit: regarding the bolt, I usually turn by hand except the last bit tightening it down. Def shouldn't be hard.
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #8 ·
Thanks. The difficulty threading it seemed strange to me too. So I will check that too. I hope I haven't damaged the threads!

Sam
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #11 · (Edited)
Doode:

After our exchange yesterday, I wondered if the reason I had a tougher time screwing the oil change filter bolt might have been due to crud on the inside (where the bolt threads onto) which may also have hurt how it was not seated properly. So this morning, I took out the filter assembly, and cleaned the inside threads with a rag and some carb cleaner. And it removed some crud from there. And I was able to screw it on a little more easily (and I also made sure that the tabs seated properly on either side). And when I started the bike, it appears that there was no leak. I will test it again in a couple of says after adding some more oil.

I was still not able to finger tighten it as you, and others, say you are able to. I have a question; When you finger tighten it, does the oil filter inside the bolt also turn along with the bolt? In my case it turns when I am tightening it - which implies that with the spring and washer below the oil filter, it is a good tight fit. But this also means that I am unable to do a finger tightening of the bolt. I also wonder after you mentioned yesterday, if one of the POs had cross threaded the bolt in the past.(I usually follow a trick I learned years ago from my dad of doing a short reverse turn when seating these threads.)

Anyway, thanks for your help! I hope this has solved it.
 

·
Registered
Joined
·
2,510 Posts
Awesome work getting it back together. Hopefully that took care of it.
As for tightening... Usually the filter housing would spin as I tightened the bolt. I don't 100% recall once the housing mated with the notch whether I needed to use extra leverage. By "finger tightening" I meant with a socket and extension only, only needed the wrench for the final snug. I don't think I ever used just my fingers.
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #13 ·
Doode:

Thanks for the clarification. I thought you meant you were able to use just fingers alone.

It was your comment from yesterday that led me to think of doing what I did today. So a big thank you to you.
 

·
Premium Member
Joined
·
24,208 Posts
My filter bolt is usually somewhat stiff when turning in. I also replace the bolt O-ring each time and I'm pretty sure that's the cause. When I haven't change that one it is fairly easy to install. I had a cover that was warped on one engine and I ended up surfacing the lip edge down @1mm to get a good seal.
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #16 ·
LDR: Thanks for sharing your experience and insights. Always valuable when newbies like me are working on a new acquisition to be aware of any quirks when doing some of these DIY stuff.
The help from this forum is very valuable and highly appreciated.

I also replaced the bolt o-ring and the filter cover o-ring/gasket. And the filter bolt was not that smooth to turn. So I tried an experiment before actually installing it the final time. I tried to turn the bolt alone in without the filter to see if the threads on the inside were the problem. And when that too was a little stiff, I decided to clean those inner threads. That may have appeared to solve the problem but I have to run the bike some more to make sure it actually has solved the problem.
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #17 · (Edited)
Update:
I topped up the oil today and ran the engine. Started on the first try with the choke on. Upon starting the engine, the oil pressure light went off, and there was no leak. Bone dry around the drain plug and the oil filter cover and bolt. The bike also seems to be idling fine steady around 1000 rpm after choke was released after only about a minute. Spec says 1200rpm +/- 100. I won't mess with the idle screw for now.
So: success - thanks to the invaluable support and help from the wonderful folks in this forum!

(HT: Doode, LDR (Jim))

I noticed that the the overflow hose is torn at the edges around the carburetor nipple and does not plug in well. It needs replacement though there are no worries since there is no gas leak from the hose - it is bone dry - but it will need to be replaced.

Do you recommend an OEM hose which I check is available at partzilla. Or is it better to get it ordered by a local Honda dealer since the price of shipping is almost the same as the price of the item?
 

·
Premium Member
Joined
·
24,208 Posts
I use the local Honda dealer for small individual items like the hose. My local isn't very good and it's easier to supply them with the part number since they seem to have problems looking stuff up for older models. Most of the counter people weren't born when the bikes were new. Larger orders I use places like partsfish.com and Western Honda which offer discounted pricing that makes up for the shipping costs.
I would adjust your idle speed up to 1200, prevents stalling as you come to a final stop when it's hot. Don't trust the factory tach for that, they're not accurate after the 1st year of life.
 

·
Registered
Joined
·
785 Posts
Yep, washer between filter and spring, they usually stick to the old filter and get trashed.

Yep, the notch and peg.

Yep, the filter is a good fit on the oil filter bolt, a seal.

Yep the filter does tend to rotate with the oil filer bolt until its nipped.

I like to grease the oil filter bolt in its hole thru the filter cover, as lots of salt is used around here.

You know the oil filter bolt torque?

How was the oil filter blockage bypass valve, stuck or free? Its sprung loaded.

Use a hex head socket.

Get a magnetic oil sump plug.

Did you examine the old engine oil for "glitter" and black bits?
 
1 - 20 of 22 Posts
Top