Bought an 02, with 4.7 from a lot. Owner just said needs motor no explanation why. Motor turns over but very hard. Oil on stick looks normal. Im new to these motors. Anything i can check to see if maybe it just jumped timing, or its something else? If its a head gasket it would still start and just run rough, no?

 

4.7s have a bad issue of overheating and blowing head gaskets or cracking heads. Why not ask the owner more questions as to why it needs a motor. It wont change the fact that it needs one.

 

ok you bought a truck where the owner says needs new engine and now is not the time to touble shoot a possible quick fix. Start with pricing out a new rebuilt 4.7 or a used 4.7 from a wrecker, now you have a ball park number on the high side of expenses.

air flue mixture, spark and compression are the three basics.

I would start with pulling out the plugs ( only 8 in your year of 4.7 ) Sparkplugs can tell you a lot in short period of time, A hynes dodge ram manual will give you the break down on the 4.7 and will have pics of spark plugs you can cross referance.

if all 8 cy are sparking and all eight injectors are working and the engine is turning over but not running, I would suspect the timming chain, you can turn over the engine by hand with a socket and a large breaker bar on the harmonic ballancer, ( timming chain aligns the camshaft to the crank shaft ( read the a haynes manual ) remove fan belt, if rotation is free and easy, than chances are good that the engine inturnals are ok.

as for the ecm ( coumputer which regulates spark and air flue mixture) I don;t have the xperties to go thier with trouble shooting.

Thiers a whealth of knowledge on this fourm so keep on checking!!

 

Thanks for the tips. The only thing i had time to do so far is squirt some starter fluid(didnt do anything). going to try your suggesting this week. I had an 02 previously that overheated and blew gasket/cracked head but still started and ran(with a miss and smoke of course) If the internals were bad in this new one, it would still at least start and knock wouldnt it?

 

really depends on how hard it is to turn over... pretty sure these motors have to spin a certain amount of rpm before the iginition system will allow it to start. if it's that hard to turn over you're probably looking at a problem with the bottom end of the engine, but that just my opinion. good luck.

 

Did you ask the seller why he thinks/knows it needs a new engine?

 

Bought the truck off a lot. All the owner said when i asked was it needed a motor, not a real chatty fella. Took 2 drivers side plugs out, put a plug in the wire and turned the truck over. didnt see the plugs sparking. Also the 2 old plugs were wore down even with the ceramic. When i turned it over with the plugs out i could hear the compression popping. im having it towed to a shop. I might get lucky and it only needs an ecm or it jumped timing. Motors around here are $1500.