!984 928 engine
 

First time posting. I have a 1984 928 is that an interference motor.

1984 16 valve engines are not, generally speaking, interference engines.

1984 16 valve Euro or ROW engines can supposedly be interference engines, but may not be.

If you have a M28-21 or M28-22 (a Euro or ROW engine), it would be prudent to treat it as an interference engine. (VIN# will have ZZZ within it)

Have I confused you thoroughly yet? :)

Thank you, I am not confused i will check my vin #.

The engine number is stamped on a horizontal plate just under where the upper radiator hose mates to the engine. It should be an M28-something. That will determine whether your engine is interference, since the engine could have been replaced at some point prior to you.

https://forums.pelicanparts.com/uploads13/engine1211118442.jpg

The blue arrow shows where the engine code is located

Either way, inspecting the timing belt system is a good first step, along with all the rubber high pressure fuel lines etc.

Absolutely true and correct!

hey graym - how or why do you know or think it's an interference engine? - did the engine crash?

Replaced the water pump and timing belt. Had everything in time, Rotated the engine 4 times just to make sure and everything was good. Started it up, was running real good. Was waiting for it to get up to temperature, Then it jumped time. I thought it was an interference motor so i pulled it out. Bought an inspection camera and put it down the spark plug hole expecting to see all kinds of damage but it doesn't look bad. In hindsight i probably should have done that before i pulled the motor. Then i was reading the forum and someone said that early engines might not be interference engines. So then another hindsight mistake. I thought i would ask. Thanks for all the help i will let you know what i find and next time i have a problem i will ask first.

Pulling the motor is an opportunity to easily do a ton things you will eventually need to do. My own perspective would be to err on the insane side of doing things while its out.

Well i finally checked my numbers on the engine they are. M 28/20 81 E 06738. I don't know what all that means, but i'm thinking that it is not an interference motor. So i will probably take it apart and rebuild it. New rings, bearings and a valve job.

M 28/20 tells us that you have an 83-84 4.7L US version engine for an AT in your car. A whopping 234 HP from the factory and not likely an interference engine. I don't know what the 81E is but the block number is 06738

Most will need head work, new valve guides etc, bottom end rarely, and due to the way bearings are sold it can be pesky to get a full set of the size you need.