2003 SXT Neon Engine Rebuild

m2736185 · Post by **m2736185** » Fri Oct 24, 2008 10:19 pm

Hey guys I need a little help rebuilding an engine. My 2000 Neon
was totalled so i stumbled upon a 2003 SXT Neon that has about
150,000 miles on it....and doesnt run because the timing belt went.
The owner days it went while the car was doing maybe 10MPH. I
am thinking if I am lucky there is no damage to the pistons and its
proly just the head that needs replacing right?

I have replaced my timing belt before and that was the longest PITA full day job ever. What I am wondering is how tough of a job
is replacing the head? Are there any "special tools" I am going to
need? Should anything else be changed while I am under there?

aperson · Post by **aperson** » Fri Oct 24, 2008 11:29 pm

You'll need a head gasket set but I'd try to find a R/T head if possible. If you search around you'll find that it has a hotter camshaft and better flowing head too. And it's a direct swap also, but you won't loose anything by going with a regular head.

m2736185 · Post by **m2736185** » Sat Oct 25, 2008 1:40 am

I am contemplating between just changing the head/rebuilding the engine or swapping the engine with a new used one. I have seen used engines with less that 50k miles going for under $400....but im having a hard time finding a 5 speed transmission.

ZeroChad · Post by **ZeroChad** » Sat Oct 25, 2008 11:22 am

Sounds like an awesome project. You're right, those valves are probably toast.
I'm thinking buying a long block from a salvage yard would be a good way to go. Lower miles on the block, plus you'll have it out of the car so you can easily build it up to spec. I'd replace the timing belt, timing belt tensioner, water pump, oil pump, and any of the seals before you put it in. That way you'll have a reliable motor for years.

m2736185 · Post by **m2736185** » Sat Oct 25, 2008 11:30 am

yea, thats what I was thinking would be the best way to go since it would cost proly less than buying a new head and all the other bs parts like gaskets and piston rings etc... the only prob is its gonna be a pain in the ass to get the engine out. I also want to put a 5 speed tranny in there, but its hard to find them for some reason.

m2736185 · Post by **m2736185** » Thu Nov 20, 2008 2:33 am

Ah well all my parts are finally here! Looks like I have a long weekend in the cold ahead of me. I am only doing a head swap for now and I was wondering once i get the head off should I try to clean the carbon buildup on the pistons? What would be the best way to do so?

Post by **occasional demons** » Thu Nov 20, 2008 8:06 am

Castrol super clean or similiar will disolve the carbon, but you may need to soak it. Mopar Combustion Chamber cleaner should work also. Then you will need to wipe it out. I would mask off the deck surface to keep debris from falling down into the oil return/coolant holes. Granted, an oil change is a must, but no need for extra crap getting into the oil pump pick up screen etc. this would be the least agressive method to avoivd scratching or gouging the piston surface. It is how I did mine. A bit messy but effective. I also cleaned/painted and installed an alternate oil pressure sende while the head was off. It is extremely easy at that point.

m2736185 · Post by **m2736185** » Sat Nov 22, 2008 5:45 am

Ah and one more thing. I used a razor to make the head and block surface as smooth as I can, but I am not satisfied. Should I also try 1000 grit sandpaper? And for the head gasket so I apply abt silicone bead to it or just lay it as is?

Post by **occasional demons** » Sat Nov 22, 2008 9:47 am

You do not want a mirror finish on the gasket surface. The gasket needs something to bite into. You will also need some headgasket sealant. Mopar sells it in a spray can. Can't recall the exact name on it, but it tells you in the Mopar head gasket kit. If you are using aftermarket go on line or call them for their recommendations if there aren't any instructions.

4318035 Sealant, Aerosol Gasket

Found here: http://www.neons.org/neontsb/TSB/09/090598.htm

It is for 1gn, but most of that should apply.

m2736185 · Post by **m2736185** » Sat Nov 22, 2008 2:47 pm

Exactly what I was looking for.
Thanks!

m2736185 · Post by **m2736185** » Sat Nov 22, 2008 7:05 pm

Alright Im going to take the day off tomorrow to get all the work done since its going to be the only nice day of the week. BTW I have been reading a few places that I am going to need a DRB scan tool to relearn the timing? Is this something new? I never used this when i did the timing belt on my 00 Neon. Can I just unplug the battery?

Post by **occasional demons** » Sat Nov 22, 2008 8:00 pm

No scan tool needed. The battery should already be disconnected! Just for general saftey reasons. All you need to do is line up the marks, and be sure you have the cam sprocket torqued to spec.!
I don't think NCG is that bad! The cam timing is mechanically locked in place by the belt, and the ign. timing is adjusted by the PCM from the fixed notches on the crank. The injector tiimng is determined by the cam position sensor.

m2736185 · Post by **m2736185** » Sun Nov 23, 2008 5:20 pm

I got the intake manifold unbolted today, but it looks like I am going to need to remove the wires from the starter to take it out. That looks like a PITA.

I was wondering would I need new gaskets for the intake manifold and the exhaust manifold?

LionheartedSXT · Post by **LionheartedSXT** » Sun Nov 23, 2008 6:19 pm

Yup just got finished doing my intake manifold. YEa you need to remove the starter positive wire, the ground on the starter, the map sensor, the sensor next to and under the starter and one that goes to the a/c I believe. So 4 sensors, the ground and starter wires. Yea it was kind of annoying.

Yea it would be wise to buy new gaskets especially if the motor has 150,000 miles on it. Matter of fact I would replace more than that. The necessary things that should be changed with that much mileage.

m2736185 · Post by **m2736185** » Sun Nov 23, 2008 6:51 pm

Well the block as 110k and the new head I am installing has 75k. Im going to use the same gaskets for now I can always replace the intake and exhaust gaskets down the road. Hopefully crossing my fingers I can get everything done tomorrow...but it looks like a 2 day job from here on. I havent gotten to the fun part of the mounts and engine plate yet.

Post by **occasional demons** » Sun Nov 23, 2008 9:53 pm

The exhaust gasket is like $5 at Autozone. I would replace that one, as the exhaust mani. is a little more work to remove, plus if it leaks, it will screw with the o2 sensor so bad you won't know WTF hit it.
The O rings on the IM, you may get lucky re using them as long as they are still soft and pliable. As for the starter wire, I removed the tape from the harness and re-routed it the last time I had the intake off. Now I don't have to deal with that in the future. Just re-tape everything and it is hardly noticable.

m2736185 · Post by **m2736185** » Mon Nov 24, 2008 12:41 am

Yea, but my autozone sux they never have any Neon stuff in stock, but I will give it a try tomorrow.

Grr I was just looking inside the intake of my new head and it looks like I got some dried coolant that was built up in there its stuck all around two of the valves. Im going to try to scrape it off with a wooden stick and then hit it with some air.

m2736185 · Post by **m2736185** » Thu Nov 27, 2008 2:58 am

Ah what a day I have no skin on my hands left! What I thought was going to be an 8 hour job turned into 12 hours and im still not done yet. I swapped heads and thought it would be cake from there..but for some reason the tensioner for the timing belt took me 3 hours to get the belt on then I couldnt get the mounting plate back onto the engine so i thought perhaps I do need to remove the engine mount after all well to make a long story short THE Engine mount torq bolt is not lining up with the mounting plate...and I think there is a part of the gromet sticking out...is it suppose to be flush? WHat is the secret I want to get this all done in the morning and cross my fingers the car starts.