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For the experts: best sender locations for oil temp and pressure


po18guy

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15 hours ago, Lucky Phil said:

Well in the commercial jet world generally speaking you don't do anything on the strength of 1 parameter failure. You look at the other parameters and if they are all normal you continue. I once had a pilot call me looking to divert to a small alternate strip because of a fuel filter clogging light on. I asked him about the other parameters, any fluctuations etc? No. I mentioned to him that these switches were prone to failure and that by the time he diverted to the small alternate remote strip with no support of any kind he'd only be 10 min from his major scheduled destination strip anyway, but it was his decision. He went for the alternate, sigh, and it took us half a day to get him out of there. You can lead a horse as they say.

Ciao  

In general aviation, only two words describe what the gauges will subsequently tell you: "dead stick."

Generally speaking, landings are then much more interesting.

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14 hours ago, pete roper said:

Phil, the oil feeds to the camboxes are internal. The lubrication circuit is all internal, it’s only the cooling circuit that travels through the hoses. The cam feeds are up the front inner and rear outer studs.

Have a couple of Kwackers. Liquid cooled DOHC and all the super cool stuff. Still has external lines feeding the head and two removable internal copper lines feeding the cams and rockers. To adjust the valves, one must remove those internal lines. Designed by a committee whose members were not speaking or, more likely, by bean counters who knew that copper lines are cheaper than intricate internal passages. All well amortised over a 25 year production run. 

Thinking back, the Ford Y-block surely could have used external lines to the top. The internal line jogged an inch or so over at the head-block junction and in that age of sludge, quickly clogged. On mine, pulled the left rocker shaft and ran it on the right bank, poking the feed with a clothes hanger until oil appeared. Did the same for the right bank and valves were suddenly quieter! 

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Ok Pete and docc got the images, very nice thanks. The MGS engine basically uses a jackshaft that has had all the back lopped off and machined down to a short 12.5 mm long stub that slips into the same sized bearing as the Griso. You then just seal off the oil feed to the rear jackshaft/camshaft bearing and save youself some oil feed and friction losses.

I'll try and post an image later.

Ciao

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15 hours ago, pete roper said:

It's a 2RS bearing.

I think I've got a pic of the lubrication system layout on the 8V.

[img]https://live.staticflickr.com/65535/49417221471_3d5c8344ac_z.jpg[/img]

This is the front, (And rear next to it.) main bearing. While I too hate the supposedly non replaceable front main I'm pretty sure I could sort out a way of fitting the earlier main and allowing the cooler delivery to the under piston sprays.

[img]https://live.staticflickr.com/65535/49417221476_65ebf9c3e5_z.jpg[/img]

You can see the gallery for the oil sprays machined into the case. The bearing is then presumably shrunk in afterwards.

[img]https://live.staticflickr.com/65535/49416747388_9073576ce6_z.jpg[/img]

The case is cross drilled for the spray feeds.

[img]https://live.staticflickr.com/65535/49417221396_e1f0e64c3a_z.jpg[/img]

The jack shaft is now withdrawn from the back unlike the earlier motors and the rear end spins in a needle roller in the cap that bolts to the rear of the case. It is sealed with an o-ring.

Thank Pete.

Ciao

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8 minutes ago, Lucky Phil said:

Ok Pete and docc got the images, very nice thanks. The MGS engine basically uses a jackshaft that has had all the back lopped off and machined down to a short 12.5 mm long stub that slips into the same sized bearing as the Griso. You then just seal off the oil feed to the rear jackshaft/camshaft bearing and save youself some oil feed and friction losses.

I'll try and post an image later.

Ciao

I thought that was done to allow for a longer stroke? I'll have to go take a looksee at the bore and stroke figures to see if I'm right. Did the MGS use big bolt Carillos?

The 1200 and 1400 'Nuovo Hi Cam' motors both have the same stroke and have the 'Full Length' front to rear idler/jack shaft as the cam drive is taken from the rear of the shaft by chain to the cams rather than the rather inelegant belt arrangement used on the early Hi Cams and MGS-01.

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11 minutes ago, pete roper said:

I thought that was done to allow for a longer stroke? I'll have to go take a looksee at the bore and stroke figures to see if I'm right. Did the MGS use big bolt Carillos?

The 1200 and 1400 'Nuovo Hi Cam' motors both have the same stroke and have the 'Full Length' front to rear idler/jack shaft as the cam drive is taken from the rear of the shaft by chain to the cams rather than the rather inelegant belt arrangement used on the early Hi Cams and MGS-01.

No Pete the MGS is still a 78mm stroke. Like the needle bearing support at the nose of the camshafts instead of the plain bearings it's a friction elimination solution I believe.I like the later 1200/1400 chain drive arrangement better as well. Neater more compact and gives the cooling airfow a straight shot at the head. 

I'm not sure if the MGS used the big bolt carrillos or not but I'd be surprised if they did. It MAY also have used slightly longer rods I need to check that. The engine I'm building wont be the same sized bore as a MGS though I'm going to use 95mm pistons and probably the same length rods as I have a set of brand new H beam rods with oil squirters for a Guzzi in the std length. I'm sure the piston manufacturer can accommodate any compression height I want though so I need to look at piston to rod ratios and see if there's anything worthwhile to be gained by buying expensive longer rods.  

Ciao

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1 hour ago, Lucky Phil said:

No Pete the MGS is still a 78mm stroke. Like the needle bearing support at the nose of the camshafts instead of the plain bearings it's a friction elimination solution I believe.I like the later 1200/1400 chain drive arrangement better as well. Neater more compact and gives the cooling airfow a straight shot at the head. 

Ciao

For those interested, here is the jackshaft from a Daytona/Centauro engine compared to the replacement from an MGS-01. The Centy jack shaft replaces the 2 valve engines cam shaft and is driven by the crank gear at the front which in turn drives 2 belt pullies mounted off the front of this shaft. The MGS-01 does away with the whole back end of the Jack shaft and plain bearing at the front of the cases and replaces it with a ball bearing. Smart move as it saves the friction of the jack shaft rear bearing and also replaces the front plain bearing with a low friction ball bearing.

DSC01162.JPG

Ciao

 

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12 hours ago, docc said:

Pete's post with the images inserted.

Hey Docc,    It's over my head and above my pay  grade, but I love reading knowledgeable gearheads really getting into it. lol.!

    Tks for snagging those  images, they're worth a thousand words to me.

 

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