| Author |
Message |
    
saltycraig
New member
Username: saltycraig
Post Number: 1
Registered: 06-2018
| | Posted on Sunday, June 10, 2018 - 02:49 am: | 
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Hi, I'm new to this forum but have a bit of a quandary.. My Simplex 6-7hp motor idles without any smoke. will run under load without smoke but when I dis-engage the gearbox and sit at idle it will begin to blow blue smoke (oil?)
Does anybody know why this might be happening?
After setting off again it will clear up in about 5 minutes!! wierd huh? |
kingfisher
Member
Username: kingfisher
Post Number: 29
Registered: 01-2013
| | Posted on Sunday, June 10, 2018 - 08:46 am: |
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No idea really.
What oil are you using? Mono 30 is recommended. Does yours have a dipstick? Is the level ok?
Mark |
miro
Senior Member
Username: miro
Post Number: 973
Registered: 11-2001
| | Posted on Sunday, June 10, 2018 - 10:02 pm: |
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This usually happens when the valve guides are worn.
Under load there is little vaccuum in the intake manifold.
But when it is idling, the throttle is almost closed, and there is higher vaccuum in the intake, and oil gets sucked up past the valve stems and you'll get blue smoke.
The simplest solution is - live with it.
Next, replace the valve guides - yuck
Next, knurl the valve stems - less yuck but still way worse than the simple approach.
Then when you re-apply load, the intake vaccuum is reduced, oil is not sucked up past the valve stems and it burns clean.
Miro |
saltycraig
New member
Username: saltycraig
Post Number: 2
Registered: 06-2018
| | Posted on Monday, June 11, 2018 - 08:46 am: |
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Thanks Miro, your answer is a great help.
I'm considering solution 2!!
are you still able to get valve guides or would they be something I would have to fabricate my-self??
Cheers
Craig |
miro
Senior Member
Username: miro
Post Number: 974
Registered: 11-2001
| | Posted on Monday, June 11, 2018 - 10:44 pm: |
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I suspect that you will not be able to get the guides as a spare part.
The trick will be to understand HOW to remove the old ones. Sometimes you can drive them into the crankcase but you may have to remove the camshaft fist ( the yuck factor). I've made custom pullers to pull them up out of the block. I did that once on a 4 cylinder and swore I'd never do another job like that ( more yuck)
But make sure that's the issue (worn guides) first before tearing into the engine.
You may want to review valve guide removal / installation manuals to give yourself some idea of the challenge.Old tractor engine manuals usually have the procedures.
Miro |
klanger
Senior Member
Username: klanger
Post Number: 128
Registered: 03-2012
| | Posted on Tuesday, June 12, 2018 - 06:28 am: |
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Hi Craig,
Simplex engines are still made in Sydney, and parts should be available.
Call them, Hardman & Hall
02 9624 6704
Kev |
saltycraig
New member
Username: saltycraig
Post Number: 3
Registered: 06-2018
| | Posted on Saturday, June 16, 2018 - 03:58 am: |
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Thanks Kev, I would also like to see weather there is a workshop manual with clearances and tolerances in it?
too much to wish for I suppose!! |
kingfisher
Member
Username: kingfisher
Post Number: 30
Registered: 01-2013
| | Posted on Saturday, June 16, 2018 - 08:54 am: |
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Simplex can provide you with a manual. About $25 by memory. May not have the detail you are looking for but lots of useful stuff.
Mark |
saltycraig
Member
Username: saltycraig
Post Number: 4
Registered: 06-2018
| | Posted on Saturday, June 23, 2018 - 07:38 am: |
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Hi guys/ and ladies I suppose.
I'm wondering if any of you know where I could get a "Roloroter" waterpump for my Simplex?
Are there reconditioning parts for them Also?? |
saltycraig
Member
Username: saltycraig
Post Number: 5
Registered: 06-2018
| | Posted on Tuesday, February 05, 2019 - 09:48 pm: |
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Hi.. Does anybody what the ring gap should be for a simplex engine?
According to the formula it should be between 16 and 18 thou for a bore size of 3 3/4".
Being an early built engine,, are the tollerance a little different?
the ring width is about 7/16ths...
Cheers |
jb_castagnos
Senior Member
Username: jb_castagnos
Post Number: 1413
Registered: 07-2002
| | Posted on Wednesday, February 06, 2019 - 07:35 pm: |
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Minimum ring gap is critical, you don't want the rings to butt and seize. Larger gaps really don't hurt, rule of thumb is .004" gap per inch of bore. Many of the old engines with pinned rings had the pin on the bottom land, this usually ended up with a 3/16" or better gap and the engines ran fine. |
saltycraig
Member
Username: saltycraig
Post Number: 6
Registered: 06-2018
| | Posted on Wednesday, February 06, 2019 - 07:56 pm: |
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Thanks Jb, thats helpful! It puts my mind at rest |
saltycraig
Member
Username: saltycraig
Post Number: 7
Registered: 06-2018
| | Posted on Saturday, February 09, 2019 - 06:28 pm: |
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Hi, I've taken the head off my engine and lapped the valves.
I also noticed the bore could do with a hone (she ran too hot for a while)
looking at the head gasket, I noticed that the threee water jacket gallereys on the front of the head are not open on the new gasket!!
Should I ensure that all jackett gallerys are clear on the gasket to allow water flow? |
saltycraig
Member
Username: saltycraig
Post Number: 8
Registered: 06-2018
| | Posted on Thursday, May 23, 2019 - 08:20 pm: |
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Does anyone know how loose or fine the setting on a model D schebler puffer valve should be?
after tuning the caby mixture , I find that under load it still runs rich (carbon build up in cyllander head).. |
ernie
Senior Member
Username: ernie
Post Number: 2524
Registered: 01-2002
| | Posted on Sunday, May 26, 2019 - 01:22 pm: |
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According to Schebler set the needle valve for a good idle. Then adjust the (in your words puffer valve) so it runs good. It sounds like you need it to be leaner at RPM which equals less spring tension.
Hope this helps
Ernie |
saltycraig
Member
Username: saltycraig
Post Number: 9
Registered: 06-2018
| | Posted on Sunday, May 26, 2019 - 07:24 pm: |
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thanks ernie, I had a sneeking suspicion that was the problem but I want some reassuence before I fiddled with an engine that is running.
Although not that well under load!!
cheers |
saltycraig
Member
Username: saltycraig
Post Number: 11
Registered: 06-2018
| | Posted on Tuesday, October 06, 2020 - 09:25 pm: |
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Hi, has anyone replaced a babbit bering wth a roller bearing??
just curios as to weather a modern bearing could do the job and if it were more benificial..
cheers |
miro
Senior Member
Username: miro
Post Number: 1102
Registered: 11-2001
| | Posted on Thursday, October 08, 2020 - 07:29 pm: |
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The sleeve bearings also act - quite importantly - as a seal for the crankcase.
I know that one of two guys have put modern seals on the crankshafts and have 'stuffed" the crankcases.
But these are really really good machinists .
Most of use simply use the sleeve bearings with heavy grease . They work and besides most of use want to spend time in the boat cruising, not in the shop machining.
Miro |
jb_castagnos
Senior Member
Username: jb_castagnos
Post Number: 1460
Registered: 07-2002
| | Posted on Saturday, October 10, 2020 - 01:09 am: |
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Roller bearings require an extremely hard shaft to run on, like a bearing race. The spot contact of a roller bearing is like a hair line, all of the pressure is on that one spot. A friend had his crank go out on an outboard, machine shop welded it with his hardest material, ground it to specs. Looked perfect, didn't last a day. |
saltycraig
Member
Username: saltycraig
Post Number: 12
Registered: 06-2018
| | Posted on Saturday, December 12, 2020 - 11:54 pm: |
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Hi, I'm wondering wheather I have set the valve timing wrong..
The ngine will run but I think it is advanced... the exhuast vale openes a lot sooner than I think it should at the bottom of the power stroke and I believe that both valves should rock at TDC?? |
sea_bee
Member
Username: sea_bee
Post Number: 6
Registered: 05-2021
| | Posted on Friday, February 03, 2023 - 09:30 pm: |
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I'm chasing an exhaust valve for a 5hp Simplex |
kingfisher
Advanced Member
Username: kingfisher
Post Number: 48
Registered: 01-2013
| | Posted on Friday, February 03, 2023 - 10:46 pm: |
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You could try ringing them. I believe they are getting out of the spare parts game but I don't know when. The company trades as GEARCO 02 9838 8931 or 0422 415 717. Good luck, Mark |
