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Lycoming piston part numbers

Posted: Wed Feb 22, 2017 7:53 pm
by grassblaster
I've used the search but can't find anything. The engine is an O-290G. The Pistons have the part number 666403 on them. What engine are they originally from and what was their compression ratio? Thanks

Re: Lycoming piston part numbers

Posted: Wed Feb 22, 2017 11:01 pm
by getitdone
Found this info online, hope it helps

HOW TO IDENTIFY JE/SRP PISTONS
All JE and SRP Pistons will have "JE" or "SRP" forged or laser engraved on the underside of the piston. If your piston does not have these marks, it was not manufactured by JE or SRP Pistons. Please use the information below to identify your piston.

http://www.jepistons.com/Images/TechCorner/identify.jpg

Job # : This 6-digit number is located on both custom and off-the-shelf pistons. Use this number to reorder custom pistons and/or locate replacement components for custom pistons (wrist pins/locks/rings).

Shelf Piston Part # : A 6-digit number beginning with P/N indicates an off-the-shelf, catalog item. Use this number to re-order off-the-shelf pistons. Custom pistons will not have this number.

Forging # : This number ONLY identifies the raw forging that was used to manufacture the piston. A large variety of bore sizes, compression heights and other design features can be applied to a single forging.

Frequently Asked Questions
What if my piston has no laser mark?

Pistons manufactured before 2004 did not have any laser marking and must be identified by another method. If the pistons are in the original box, there is a label located on the side of the box that identifies the job number and the piston part number. If you do not have the original box, try to locate the original JE/SRP invoice.

If you have no documentation for your JE or SRP Pistons, you can mail a sample to JE Pistons to reverse engineer. If you’re sample is followed by an order for a set of pistons, there is no charge for this service. NOTE: If no order is placed, there is a one-time $75 layout fee for this service. Please allow 3-5 days for reverse engineering.

If you would like JE to reverse engineer your piston, please mail a single sample piston, your contact information and a method of payment to:

JE/SRP Pistons
Attn: Piston Identification, Engineering
10800 Valley View Street
Cypress, California 90630
USA

I have located the job/order number, now what?

If the piston only has the job/order number on the pin boss, it is a custom piston. If you want to place an order for custom pistons, you can call the JE Pistons technical sales department or a JE Pistons distributor. Provide the 6-digit job/order number and list the features you would like to change (bore, compression distance, etc.) on the custom piston order form located here.

I have located the Shelf Piston Part number, now what?

You can order replacement pistons and accessories from your JE Pistons distributor or directly from JE Pistons by adding the item number to your shopping cart.

Online Shelf Stock Order Form (existing customers):


Order Desk: Tel: (714) 898-5114
FAX: (800) 5PISTON
orders@jepistons.com

Re: Lycoming piston part numbers

Posted: Thu Feb 23, 2017 7:45 am
by pirate
According to this link...http://home.jps.net/~eeicorp/id40.htm it should have the same compression as a O-290-D which is 6.50:1

Re: Lycoming piston part numbers

Posted: Thu Feb 23, 2017 6:23 pm
by grassblaster
Yes sir but I'm fairly certain the engine is not stock.

Re: Lycoming piston part numbers

Posted: Thu Feb 23, 2017 7:02 pm
by pirate
And your reason for believing this is?....The bore of the O-290 is 4.8750 in and the stroke is 3.875 in...nothing is going to change this unless it's bored out.

There are 6 different O-290 certified aircraft engines. The O-290-D /11 /D2 /D2A /D2B / and D2C. Then there's the one you have which is the G or ground powered version. They all either have 6.50:1 or 7.50:1 compression ratio. The one you have originally had an O-235 crankshaft which they (Lycoming) suggested be replaced if going to a higher compression than 6.%0:1

The other option is someone replaced the O-290 s/v cylinders with O-435 a/v cylinders which has the same bore /stroke and also replaced the s/v pistons with a/v pistons

Feel free to believe what you wish. It is what it is.

Re: Lycoming piston part numbers

Posted: Fri Feb 24, 2017 6:42 pm
by grassblaster
Take your attitude somewhere else I addressed you with respect sir. The reason I believe it's not a stock engine is as a kid I was told my grandfather built the engine and the it was no longer stock. As a kid riding the boat with my dad I remember it having plenty of power on an 11' gore hull with fairly heavy square tube rigging. We went where we wanted. If I had a pic of the Pistons I would post it, they have a considerable dome.. That's the reason I posted the part number, to find out what the piston is. Not to get attitude from you because I didn't just accept what some website says it should be in stock form..

Re: Lycoming piston part numbers

Posted: Fri Feb 24, 2017 10:54 pm
by pirate
I apologize if I hurt your feelings....My bad....I should never have used facts to answerer your question.

Re: Lycoming piston part numbers

Posted: Sat Feb 25, 2017 10:27 am
by pirate
You'd be surprised at what you can learn off of "some website." Here's more information from one of them....

http://www.supercub.org/forum/showthrea ... c3d31a4292

Re: Lycoming piston part numbers

Posted: Sat Feb 25, 2017 11:25 pm
by grassblaster
No sir no hurt feelings here. Just didn't like the attitude implied in your post. And although you are correct the links you shared have some really neat info. What you are failing to understand is I would like to find info for the specific piston part number I originally listed.

Re: Lycoming piston part numbers

Posted: Tue Feb 28, 2017 12:17 pm
by pirate
No sir no hurt feelings here. Just didn't like the attitude implied in your post. And although you are correct the links you shared have some really neat info. What you are failing to understand is I would like to find info for the specific piston part number I originally listed


Sorry you had a problem with my attitude, I get like that when I try and help someone find something based on incorrect information. What you are failing to understand is that the number you posted is probably a casting number instead of a part number. I supplied those links to help you figure out what you were looking for. Good luck.

Re: Lycoming piston part numbers

Posted: Tue Feb 28, 2017 12:33 pm
by grassblaster
I call bull****. Those links gave no references to those being casting numbers. Anyway thanks for the non information.

Re: Lycoming piston part numbers

Posted: Tue Feb 28, 2017 12:47 pm
by pirate
Call bull all you want ace. If you still believe 666403 is a part number, take it up with Lycoming. Here's a copy of the e-mail they sent....

Unfortunately, the number that you have provided must be a casting number of some sorts, as I was unable to identify the part based on this number.

Kind Regards,
Heath Johnson
Field Service Technical Representative
Lycoming Engines, a div. of Avco Corporation


Like I said I sent to those links as an example of what could be done with the O-290-G. Thought it might give you a clue as to was used. Guess not. Believe what you like......and have a nice day.

Re: Lycoming piston part numbers

Posted: Tue Feb 28, 2017 3:46 pm
by grassblaster
Lmao you could have saved us both a bunch of time and just posted the reply from lycoming instead of beating around the bush... At least now I have some actual useful info about the numbers. I appreciate that. Thanks.

Re: Lycoming piston part numbers

Posted: Tue Feb 28, 2017 4:31 pm
by pirate
If you'd really done a search, you would have contacted Lycoming yourself or at least learned something about the engine from the internet. I Wasn't beating around the bush. I Thought the links might make you think a little and try and figure it out for yourself. So much for that. The younger generation doesn't want to think.....they want to be spoon fed. I usually try and help support those who support this site so I shouldn't have become involved in the first place. My bad. :banghead:

Re: Lycoming piston part numbers

Posted: Thu Mar 02, 2017 7:11 am
by krazymatt
Do they have reliefs cut in the tops for valve clearance? Could be pistons from a go435 or vo435

Re: Lycoming piston part numbers

Posted: Sat Mar 18, 2017 8:02 pm
by chugalug
Most Lycoming part numbers have 5 numbers in it, Cont. engines have 6 numbers. There probably are exceptions to this.