Engine Loud Bang

mustangman9530

New Member
May 5, 2015
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hey guys o am new to the site and just needing some opinions. I have a 1998 mustang 4.6 sohc. O have had a ticking noise for awhile and I just let it go thinking it was no big deal and last week I was cruising about 80 and all of a sudden I lost all horsepower and heard this very loud banging noise. I only lost power for a split second but now the low ticking has turned into a lout clanging noise. I used a screwdriver and determined it was coming from around the front side of the right of the motor. I did a compression test and all cylinders held 150-155 lbs. Except number 1 which held 135. I also have white smoke from tailpipes. I started tearing the motor down and I got the timing cover off last night no broken guides or chains to speak of all rockers/valves look good. What is going on?
 
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Nothing is impossible. But you are looking at a total engine rebuild if it is a rod. My son's Cobra had a rod knocking and I got quotes of 4 grand to fix. Block may need to be milled if it is even salvageable. Found a used engine for $2800.
 
Ok so once I get the heads off will I be able to see if the rods are broken or messed up? Planning on doing all the work myself. The way I see it is I can't mess it up anymore right lol.
 
ok ya sounds a little to pricy for my blood. But I have been doing all the work myself and plan on doing the rest I plan on getting at least the right side head off tonight. what do I need to do verify that it would be a rod?
 
Did you take your heads off? If you didn't yet, start the motor and remove the COPs one at a time. The rod knock should stop when you take the right cop off.
Ok new problem. tore engine completely part replaced rod bearing. Put everything back together and now won't start. I didn't mark anything timing wise so I am fairly certain that timing is the monster. Car does turn over and one Time backfired pretty sure because I primed the lines too much as I was trying to fill the lines up from where I emptied the fuel lines. Anyways I was hoping for a very very detailed guide on how to reset my timing plz help.
 
Timing is critical on these engines. If you continue to try to start it, you chance a valve connecting with a piston which could cause piston breakage, rod damage, valve damage, cam damage, etc. I just rebuilt my 4.6 with a DSS 5.0 Stroker kit due to valve clearance issues. Mine failure was caused by having too big a cam and not enough clearance between the valves and the pistons at high speeds.

I would highly recommend you get a Chiltons and follow the exact steps to install your cam chains. to the timing marks. There are two links on each chain which are brighter/shiner than the others which is how you align the cams TDC to Piston #1 TDC.

Cam Installation Good reference site with pics!
Good luck!