Is it likely that my motor is done? (timing chain issue)

[Weaver]

I have a 2003 Mercury marauder with the bottom half of the motor a 5.0 stroker motor bought from modularmustangracing.net. For whatever reason, I was driving and the engine died. I immediately stopped the car, but I have tried cranking it numerous times since then. My friend looked at the car, and he's sure its a timing chain issue. The starter spins the crank freely and you dont hear the compression like you normally would.

The local shop (who cant even tell me if my motor is an interference engine) is saying my engine needs a complete rebuild. Is this true? Can't I just get a timing chain kit for the car and repair it? It seems unlikely to me that a broken chain can lead to complete engine failure.

Thanks for any advice.

[martyo]

A broken timing chain can cause anywhere from a little to a lot of damage.

Tear the motor down and see what is doing.

[J-MAN]

Curious, how many miles on the MMR motor? Did you reuse your old chains and tensioners or go with new?

[MOTOWN]

Im curious as to how many miles as well, but as stated a teardown is in your future to see what's going on

[LANDY]

A broken timing chain can cause anywhere from a little to a lot of damage.

Tear the motor down and see what is doing.Best advise.

[Granddaddy Marq]

It Is Not A Clearance Motor! Had timing chain problems on an 01 Cobra. It will clear once the valves bend and the pistons gate little dents in them.

[Curless]

Yep, if it is the timing chain, there are issues...you may not necessarily need a rebuild but you can be sure that the valves are not happy...make sure you look very closely at the ring land area, make sure the pistons did not get hit too hard and pinch the rings...

[Weaver]

Ok well that's what I'm going to do. I'm going to tow it back home and start tearing it down when it gets a bit warmer.

[MyO4Rawdur]

I had a car that my timing chain snapped into a few hundred pieces and threw my tensioner down into my oil pan.. trust me the damage you dont see is what hurts the worst so be sure to check everything and buy some powerful magnets to get as much of the little shavings as possible.

[Weaver]

So.. My timing chains look great. My timing gear, however not so good since the woodruff key sheared. Also, I learned what a woodruff key is.

I pulled the heads off to check the pistons and valves. They definitely smacked each other but the forged pistons seemed to take it pretty well. The valves are screwed. You can kind of see the impact mark on the pistons at about the 11 and 1 O'Clock positions. The plan is to keep the block as is and get a valve job from Eddie's in Sayreville, NJ on a friend's recommendation. I seem to remember seeing blurbs about a racing valve set... if that is a thing, does anyone have a link to it? Yes I tried searching the forums..

tricky question about miles since I got a new shortblock and kept the original heads. About 120k on the body+heads, 30k on the shortblock.

[justbob]

So.. My timing chains look great. My timing gear, however not so good since the woodruff key sheared. Also, I learned what a woodruff key is.

I pulled the heads off to check the pistons and valves. They definitely smacked each other but the forged pistons seemed to take it pretty well. The valves are screwed. You can kind of see the impact mark on the pistons at about the 11 and 1 O'Clock positions. The plan is to keep the block as is and get a valve job from Eddie's in Sayreville, NJ on a friend's recommendation. I seem to remember seeing blurbs about a racing valve set... if that is a thing, does anyone have a link to it? Yes I tried searching the forums..

tricky question about miles since I got a new shortblock and kept the original heads. About 120k on the body+heads, 30k on the shortblock.

I felt your pain last week when I did this to mine in only 200 miles... Oops.
http://img.tapatalk.com/d/13/04/08/duqa5e5u.jpg

You need to figure out what decided to stop before you just throw it back together. I had just had a valve job, Manley valves, and Crower cams installed, it was I who hosed up my own work leaving out the intake cam gear spacers.. See what tired does?

http://img.tapatalk.com/d/13/04/08/4uty8yqa.jpg

This was in my oil pan of my 3500 mile short block.

http://img.tapatalk.com/d/13/04/08/jujyza4u.jpg

Anyways an hour and a half at the head shop, again, and they simply replaced the bad valves, checked everything over and I buttoned her back up last week for the Louisville meet with a brand new Ford Racing timing set. 1,300 hundred HARD miles later, and I mean hard, and she still purrs like a Lion.
I was actually grateful and somewhat relieved to find the cause of the carnage which needs to be your step 1.

Could be a bad tensioner, bad pump, ETC.


Good luck in your findings.


Self proclaimed Builder Of Badassery.

[RacerX]

Bobs right. Tear the block down too. You could have a bent rod, bearings could be squished down in a spot where they took the jolt. You have it this far apart, really not much further to go. Surface hone, re-ring, check everything for straightness, replace bearings all around. Oil pump and rotors ok?

[justbob]

I wouldn't tear the block down. Mine took a hell of a hit and I drive it two miles home pouring fuel right out of the left side tip and no rotating intake cam and all is fine. I took the head off, cleaned up the top of the pistons, and they still looked new. These forged engines can take some ridiculous abuse.

I had reused my timing chains with 92,000 miles on them the first time around. What a major difference when compared to new, regarding tensioners.


Self proclaimed Builder Of Badassery.

[RacerX]

I dunno, it's that far apart... Nothing worse than having to go back and do it again. Nothing to a shortblock teardown, really. Personal choice and time/money constraints I suppose at this point. With 30k on the sb, I would do it.

[lji372]

i envy how you guys with the experience think nothing of ripping these things apart:bows:

[Ozark Marauder]

So.. My timing chains look great. My timing gear, however not so good since the woodruff key sheared. Also, I learned what a woodruff key is.

I pulled the heads off to check the pistons and valves. They definitely smacked each other but the forged pistons seemed to take it pretty well. The valves are screwed. You can kind of see the impact mark on the pistons at about the 11 and 1 O'Clock positions. The plan is to keep the block as is and get a valve job from Eddie's in Sayreville, NJ on a friend's recommendation. I seem to remember seeing blurbs about a racing valve set... if that is a thing, does anyone have a link to it? Yes I tried searching the forums..

tricky question about miles since I got a new shortblock and kept the original heads. About 120k on the body+heads, 30k on the shortblock.

Might be this?

http://www.mercurymarauder.net/forums/showthread.php?t=70531

OZ

[nh muscle]

I say new motor from the ground up I have no regrets. Heck I even got a new computer out of it!!

[massacre]

I can't believe Marauders use 2-piece crank gears! I thought they came with the 1-piece crank gear. Glad I got one for my motor, I had heard of these horror stories.

Sorry to see so much destruction you guys, that is a bummer.

OP, if the cams on one bank stopped turning and the crank kept spinning, you def have bent valves. How many depends on where the cams were when they stopped turning. If the other bank kept spinning normally, it's possible that bank is fine and no valves were bent on that side. A leak down test can tell you how many valves are bent and which cylinders.

[Weaver]

i envy how you guys with the experience think nothing of ripping these things apart:bows:

Yea I agree. Intimidating for a non-mechanic. Luckily I have an experienced roomate who is kind enough to help. We'll both be learning on the timing portion though. Yikes!

Thanks for the link, Ozark Marauder!

[justbob]

It's much easier than reading any write I have ever read. It all makes sense once your in there.


Self proclaimed Builder Of Badassery.

[na svt]

I can't believe Marauders use 2-piece crank gears! I thought they came with the 1-piece crank gear.

All Marauders came from the factory with a one piece crank gear. Also, the pic of his crank gear shows that is a one piece.

[Weaver]

The only thing that troubles me at this point is I haven't found any real cause of this failure; just some moderate wear on the primary and secondary chain guides. Crank spun just fine when I was inspecting it. A visual inspection of the bottom end didn't turn up anything unusual.

However, I did notice some crankshaft end play, going to have to get a dial to check it; hopefully its within spec. If not, whats that mean? Im thinking new bearings and rod bolts at a minimum, correct? The mains are ARP.

I had the heads taken to a machine shop where they were reworked with new valves and came back looking pristine. I cleaned up the shortblock (carbon) and have the heads mounted. The cams are put back in, just waiting on a timing chain kit and camshaft cap bolts to come in.

I've read the procedure for setting the timing and practiced it with the old parts (no rockers installed). It seems I'll be able to do the timing job without the special tools, could I be missing something? It seems very straight-forward... Basically index all the cams in the same orientation, put on the secondary chains, then just match up the copper links on the chains to the index marks on the gears with #1 at TDC; right?

Any advice?

[Weaver]

Also, it didnt occur to me to remove the oil pump and check it while I had the oil pan off, should I remove the pan/pickup/pump and inspect it? It occured to me that I could get most of the motor together and then crank the motor outside of the car with the starter to actually "look" and see oil moving in the engine, thoughts?

Could a sudden drop in oil pressure from a pump failure have caused the chain tensioners to give slack to the chain... allowing enough of a variation in timing to cause the pistons to slap the valves... causing a jolt to the crankshaft timing gear... causing the shearing of the woodruff key?:eek:

[na svt]

However, I did notice some crankshaft end play, going to have to get a dial to check it; hopefully its within spec. If not, whats that mean? Im thinking new bearings and rod bolts at a minimum, correct? The mains are ARP.
Why would you need new rod bolts?


Basically index all the cams in the same orientation, put on the secondary chains, then just match up the copper links on the chains to the index marks on the gears with #1 at TDC; right?
You got it.

[Weaver]

Why would you need new rod bolts?


If the main bearings need to be replaced, wouldnt i have to remove the rods to get the crank out? and so wouldnt I have to remove the rod bolts? Or are you saying they are reusable?

[na svt]

Rod bolts can be reused.

[Weaver]

Crankshaft end play is good at .009, tested in 4 different positions with a digital dial indicator. Oil pump was pulled off and is good per a visual inspection.

But I just noticed some wear on the metal part of the right upper chain guide. I've looked for what could cause this but I'm just coming up with results for rattling noises. Our only theory right now is that the cam chain somehow got that far and wore it down a little, but there's about an inch of clearance and the chain is not really loose.

[justbob]

I think you are looking at a faulty secondary chain tensioner. When your cams rotate one will always be wanting to turn before or after the other one due to clocking of the lobes and spring pressures. Looks to be stock cams correct? I have aftermarket cams and upgraded valve springs and when one of cams want to rotate, the power behind the springs is utterly ridiculous.. It will gash your finger wide open between the wrench and what ever it throws you into!

I would almost assume this is where your troubles began, assuming you have good oil pressure.


Self proclaimed Builder Of Badassery.

[DWSTANG67]

Also, it didnt occur to me to remove the oil pump and check it while I had the oil pan off, should I remove the pan/pickup/pump and inspect it? It occured to me that I could get most of the motor together and then crank the motor outside of the car with the starter to actually "look" and see oil moving in the engine, thoughts?

Could a sudden drop in oil pressure from a pump failure have caused the chain tensioners to give slack to the chain... allowing enough of a variation in timing to cause the pistons to slap the valves... causing a jolt to the crankshaft timing gear... causing the shearing of the woodruff key?:eek:

dont let mick install the oil pump

[Weaver]

Well, thanks for the advice all. She drove loud and strong for a few weeks. Looks like I didn't take any pics or vids :-/. Unfortunately just a few nights ago, I got this tapping noise much like MontyD (http://www.mercurymarauder.net/forums/showthread.php?t=87251). I'll be starting a separate thread on my issue so I don't hijack his.

[alex.pitbull04]

Hi my name is Alex I just bought my 2003 Mercury Marauder I'm trying to find the brackets put my Eaton supercharger from A 03 Cobra and I can find it if anybody can give me a tip please send me a message or call me at 786 259-3996

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[alex.pitbull04]

Hey do you know where I can find the brackets to put my Eaton supercharger from 03 Cobra to my Mercury Marauder please somebody give me a tip I just call my baby I would like to put my supercharger but I don't know how

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[RF Overlord]

Not only have you resurrected an ancient thread, but you're in the wrong forum...try posting in the power-adders section.