[03-P71]

Hi, I have 03 P-71 that developed a timing chain noise!!! oh what a surprise from a 120,000 mile SoFla police car. But wait there's more. The noise started out of the blue about 4 years ago. ( not a daily driver). After researching I installed a Cloyes timing chain kit including adding ARP bolts. It made no difference with the noise but the O2 sensors reading started behaving the same (different story). When it starts cold it runs like a new engine. It's the EAOT restart that the rattle occurs from the passenger side.. The engine needs to set about 10 to 15 minutes and when started it sounds like the chain is about to come off (slight exaggeration). If the engine is restarted prior to the dwell time, no noise at all. If it sits for a couple of hours it restarts no noise. I can not find any oil schematic anywhere for this engine including Ford's own service manual (Helm). During the install of the new parts I though I had found the cause in the drivers side hydraulic tensioner, the was seal split. I figured the oil leaked out and did not work until the engine refilled it with oil. After the new components failed to fix it I took it apart again and went over it again to makes sue all the parts were in the right place. It's had about 6000 miles running this way (@126K). It has not worsened or gotten better with use.
Now I hear tale that there is a restrictor (the word used) in the passenger cylinder head. If it was a check valve to hold oil in the head that would make sense (to me) if it were stuck open. But he did say "resticto"r that is supposed to lower the oil PSI to half in the heads ???? The car has some other issues develop in the last two years that also need addressing. Long story short I loaned to my Dad for the last two years and he doesn't believe in fixing cars or maintaining them.
I really like the car and bought it about 8 years ago and had been trouble free for the first 4. My plan is to restore the vehicle to a little better than new with sensible mods (to all systems) that add a degree of performance but also may add to economy. I just brought it back to SoFla on the Fla, Turnpike and it got 29 MPG.
Any thoughts or suggestions will be much appreciated Thanks.

 

[03-P71]

This P-71 was used to chauffer dignitaries from Miami to Tallahassee. I guess the vinyl top was added so they didn't feel like they were being hauled in a cop car.

 

[CatSkinner]

Could be just time for a rebuild, particularly the heads. The engine probably has a lot of idle time. I'd wait to see if someone else chimes in before busting loose bolts, though.

 

[03-P71]

Could be just time for a rebuild, particularly the heads. The engine probably has a lot of idle time. I'd wait to see if someone else chimes in before busting loose bolts, though.

Thank you for the input. I was leaning in that direction. Problem is for me this engine is an alien. The Mercruiser uses the GM based small block (350). Cast iron, one cam, MPI. It is one hell of an engine to survive and last as long as they do in a saltwater environment. The GM engine I really like but that's as far as my affinity for GM goes.
If I could find an oil schematic maybe that would help determine what needs to be done, It just runs so perfect less the hot start rattle.
I am also weary of having the cylinder heads rebuilt and putting them on a used bottom end. But maybe that is an acceptable practice for these engines

 

[CatSkinner]

It's not a 4.6L?

 

[03-P71]

It's not a 4.6L?

4.6 Aye I was referencing the engines Iv'e worked on professionally for 28 years "ye old Chefvy 350" evolution to the current GM CI small block in a marine applications.
The rules are different for this SOHC engine from Ford. It runs so dam good I'd hate to have this issue cause long term or short term damage.

 

[CatSkinner]

Well, they're all just V-8 engines. You can get 4.6\5.4 engine rebuild guides on Amazon. There's also AllDataDIY.com on line.

 

[03-P71]

Well, they're all just V-8 engines. You can get 4.6\5.4 engine rebuild guides on Amazon. There's also AllDataDIY.com on line.[/QUO

I have a guide downloaded primarily invested in HiPo and agian talks a little about the oil system but no mention of an issue such as mine. Like I said it runs so good my issue I think is one that maybe repaired with out the shot gun fix. But as last resorts I'll tear it down but considering that takes time and a bucket of money to do I'll be patient see see what comes of the inquiry. I'd hate to "rebuild it and have the same problem, say do to some Ford only knows mystery. We get those un rebuild able engines and whatnots in the marine biz. People who don't know it's junk waste their money polishing a turd.