scott17

Anyone have these? I can't find mine.... Mostly wondering recommended fuel and prop....

rainedave

My Feedback: (1)

I ran mine with a 7x4. A 7x3 might be better. Just use a ton of castor oil, like 25% or more.

David

scott17

I ran mine with a 7-3 and 15% nitro 23% castor. It worked pretty good, just wondering if it would pull a 7-4 and maybe if it would like lower nitro....

jaka

Hi!
Ran mine 46 years ago (nine at the time) on 0% nitro! It was terrible to start for a kid!
5% nitro would be fine. Have one of those engines new in box!

stg61abc

Hi Scott. A great friend of mine, has a Pet 099 that is used on a small C/L stunt ship. The engine is very good, and the best props that we found fot it are 7X4 and 7X5. He´s using 10% comercial fuel with added castor oil to bring it to 25% total oil level. IMHO the best oil for it is all castor oil without any synthetic

cheers

Bax

My Feedback: (11)

If you send an email to the address below, we may be able to help you out.  Very likely an old hard-copy will need to be photocopied, so there may be a charge.

Bone

I have an OSPet .099 but it looks slightly more "modern" than Raindave's - was there an III model?

Still have the instructions, a friend has borrowed them at the moment so I won't be able to scan the instructions until Thursday this week. Send me a PM &Iwill email to you as a PDF

rainedave

My Feedback: (1)

Yes, there was a Pet III. The OS timeline shows a date of 1971. The Pet II was apparently introduced in 1959.

I've been looking for a pet III since I have the muffler for it (won't fit the II).

David

Bone

Good work Dave - yes, that's my engine, the OSPet III. I recall purchasing it new in 1973. Had it in a control line plane & the Pet was a good performer

How ironic! - I lost my muffler & the retention spring back in 1975 (fell from my flight box at places unknown) & have never seen a muffler/spring since oh well..........

ROBERTADAMS

I have the instructions for the OS PET II .099. I just picked up this engine with original box, instructions, and carb (called the "speed controller" )on ebay last week. Will scan as pdf file later today. Does anyone know a source of gaskets or do I need to cut my own.

ROBERTADAMS

Scott: leave your email address & I will send you the instructions for the OS PET II .099

scott17

[email protected]

scott17

I may have gaskets, which ones do you need?

Phill D

Hello Robert - i realise this is a way old thread but i would like to try to find the part number for the OS Pet .99 Conrod. I have a broken one. Is there any chance you still have this information and could either send it to me or quote the part number. I have the original measurements and engineering drawing from OS in Japan but cant find the part number as way way old. Many thanks

Phill Downey
Buderim SEQ
[email protected]

paquo

Hi all!

I've just received a couple of OS PET and one of them has the prop nut missed... I'm trying to find what thread could be... any clue? Phill Downey mentioned that he have engineering plans for these little engine... Would be great if you could share with me as I also need to know what thread were used for the 4 head screws... It seems that head of mine was removed and the screws are in bad shape...

Thanks!

paquo

Hi,

Thread of shaft is M5.

Thanks anyway.

Carlos67

I would love a set of instructions please.

[email protected]

Also if anyone reading this has any original gaskets for the PET II - there should be three gaskets. The rear "Triangle" rear cover gasket, a head gasket and a the one piece steel cylinder base gasket.

It would be great if someone you put a vernier on the thickness of each of these gaskets (preferably new gaskets but used is better than nothing). Two are very critical, the head gasket and the base gasket as it sets the intake and exhaust port timing, make a gasket the wrong thickness and your going to have problems starting and running these engines and it obviously effects the compression as well.

Just in the process of rebuilding one of these that has sat in a box for over 20 years but the gaskets are stuffed. I made some gaskets at the time but this engine never ran properly. I would say that this engine would have been a failure from the point of view of this base gasket as you would definitely have needed to replace it if you ever disassembled the engine as its so thin on the intake port its not funny.

Carlos67

The shaft thread is definitely not M5, nothing on this engine is metric. M5 may be close but it will be a BA thread like 2 BA thread to be exact. Yes an M5 nut goes on it but it wrong the shaft is only 4.65mm in diameter the nut is as loose as so 2 BA is 4.70mm x 0.81 mm.

If anyone has a OS Max 099 user instruction manual I would love a copy as I'm trying to rebuild one of these for display in my collection.

[email protected]

Carlos67

The shaft thread is definitely not M5, nothing on this engine is metric. M5 may be close but it will be a BA thread like 2 BA thread to be exact. Yes an M5 nut goes on it but it wrong the shaft is only 4.65mm in diameter the nut is as loose as so 2 BA is 4.70mm x 0.81 mm.

If anyone has a OS Max 099 user instruction manual I would love a copy as I'm trying to rebuild one of these for display in my collection.

I cannot leave my e-mail address here, it will not post my message so if you have a link or e-mail I will contact you.

This Forum is a little strange in that it doesn't appear to have a PM button so you can contact people via this site.

Holmatas

Hi Carlos,
did you ever get a reply for the thickness of the gaskets in the Pet 099 engine ?
I am also rebuilding one and can get any info on gasket thicknesses. Any advice appreciated.
cheers Mark.

Carlos67

Reply as follows from the E-Bay seller:-

Good Afternoon,

Thanks for the email. The gaskets that I sell are from samples that were sent to me from an engine builder. The head gasket is in fact a .35mm karropak material, the original head gasket (metal) is .31mm, while the base cylinder gasket original is .29mm, and cut with .25mm flexoid material.

My laser cannot cut metal and have been selling head gaskets with this material since 2005 with no issues.

I appreciate the information you provided.

Holmatas

Hi Carlos, thanks for the reply.
Do you have a contact for this seller ?
cheers Mark.

Carlos67

For anyone interested here is a pic of the conrod if they want to make one.



The critical distance is the hole centres which is 22.4mm (+0.2mm/-0.00mm). You can measure your own wristpin and crankpin easily enough but if the rod is broken or worn you need the centres.

Carlos67

For anyone considering making their own conrod for the OS PET II.



The picture is unfortunately of low resolution but I think we figured out the pitch of the holes or hole centres is 22.4mm (+0.2mm/-0.00mm) . The rest you can measure but if you have a busted or worn rod the centres are what you need.

If anyone comes across a rod from another engine that's pretty much identical, then post what engine its from. Plenty of cheap motors now coming out of China and who knows one of the rods from a current production engine may fit. The OS Rod is cast aluminium so not exactly top of the line 7075 T6 or something fully machined from bar stock that you would expect these days.