98ZJ 4.6L Stroker Build

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purple_jeep
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Re: 98ZJ 4.6L Stroker Build

Post by purple_jeep »

gradon wrote:Film on the butterfly is usually oil sucked in from the front valve cover line. I need to install a map line on my adapter. What did you use?
I used a small piece of metal pipe and mounted the MAP sensor on the throttle cable bracket.

Cheers

Chris
purple_jeep
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Re: 98ZJ 4.6L Stroker Build

Post by purple_jeep »

Oil report is still bad, will be compression testing, cylinder leak testing and looking at the valvetrain this weekend...
Oil Report 5.jpg
Cheers

Chris
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SilverXJ
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Stroker Displacement: 4.6L
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Vehicle Model: Cherokee
Location: Radford, Va

Re: 98ZJ 4.6L Stroker Build

Post by SilverXJ »

Aside from the bad oil analysis how does it run? Any odd noises?
purple_jeep
I made it to triple digits!
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Posts: 108
Joined: July 30th, 2014, 1:29 pm
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Re: 98ZJ 4.6L Stroker Build

Post by purple_jeep »

It seems to run ok, I still feel like it should be stronger but that could be due to my mild cam and lack of ported head/valve size.

Noises:
Has a whistling noise which I assume is from the new intake system, also once I installed the new intake it developed a clicking noise as it cools down which never was there before. After switching off for about 15 mins it will click every min or two.

Compression test (Engine hot):
#1 - 170
#2 - 165
#3 - 175
#4 - 178
#5 - 170
#6 - 170

Leak down test (Engine hot):
All cylinders indicated a 10-13% leakage and it seemed to be coming out the valve cover so I assume piston/ring leakage not valves. All tested within a few psi of each other. I believe this is ok?

Cheers

Chris
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SilverXJ
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Stroker Displacement: 4.6L
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Vehicle Model: Cherokee
Location: Radford, Va

Re: 98ZJ 4.6L Stroker Build

Post by SilverXJ »

purple_jeep wrote: Noises:
Has a whistling noise which I assume is from the new intake system, also once I installed the new intake it developed a clicking noise as it cools down which never was there before. After switching off for about 15 mins it will click every min or two.
Whistling noise is to be expected with a CAI, especially with a bored throttle body. Some throttle bodies do it more than others, depending to the creator's attention to detail. Clicking sound is interesting though.
Leak down test (Engine hot):
All cylinders indicated a 10-13% leakage and it seemed to be coming out the valve cover so I assume piston/ring leakage not valves. All tested within a few psi of each other. I believe this is ok?
Yes, air escaping through the valve cover/crank case/oil dipstick its ring seal. However, refresh my memory, do you have forged pistons? Did you try it with the engine hot?
purple_jeep
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Re: 98ZJ 4.6L Stroker Build

Post by purple_jeep »

Yes Icon Forged Pistons, Engine was warm not hot, had been off for about 1.5-2 hrs by the time I got the last cylinder leak tested. I did the compression test first and then had fun trying to workout how to get the correct cylinders to TDC on compression stroke for the leak test.

Throttle body is not bored but is a 68mm unit.

I took it to the shop who did my engine machining (I did the actual rebuild) and all they said about the clicking was it sounded like the noise some performance engines make as they cool but I am not sure why a new intake would cause it to start happening...

Cheers

Chris
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Re: 98ZJ 4.6L Stroker Build

Post by CandyCaneXj »

Does that clicking have almost an echo sound? Like it's on the inside of metal? It's probably the intake manifold cooling off. Alot of the 99+ ones do that because they have such a large area of flat metal underneath without webbing. It probably microscopically flexes from temperature change. I never heard a 91-98 one do it. Mine did it for 40,000 miles exactly what you are describing with the time intervals. Open the throttle body by hand and put your ear there and wait for it. I definitely would not worry about that.
purple_jeep
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Re: 98ZJ 4.6L Stroker Build

Post by purple_jeep »

Can definitely hear the click clearly from the throttle body opening so your explanation works.

Also another question, what should my spark advance be? it seems to be 15-20 at idle and 30-35 at speed does that seem right?

Is that something my tuner (flyinRyan) would adjust?

Cheers

Chris
purple_jeep
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Re: 98ZJ 4.6L Stroker Build

Post by purple_jeep »

Finnaly got a Snap-on "Red Brick" which has extended PID for the Jeep 4.0 so I was looking at all the fun stuff I can access now and one parameter that I was wondering if it could be an issue was sync between crankshaft and camshaft, most of the time it shows ok but sometimes it reads Sync Lost.

I think I will put a scope on the two signals to see if they are in sync or now.

Cheers

Chris
purple_jeep
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I made it to triple digits!
Posts: 108
Joined: July 30th, 2014, 1:29 pm
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Re: 98ZJ 4.6L Stroker Build

Post by purple_jeep »

New oil report, Maybe its better?
Oil Report 10.jpg
Have not had time to check the Crank/Cam signal

Cheers

Chris
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SilverXJ
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Stroker Displacement: 4.6L
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Vehicle Model: Cherokee
Location: Radford, Va

Re: 98ZJ 4.6L Stroker Build

Post by SilverXJ »

Maybe its just some excessive wear in. You can't really check much with out a full tear down.
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