Seafoam W\o changing oil?

[bugman53]

I just changed my 1994 jeep grand Cherokee with the 5.2 over to 0w-40 Mobil 1 after doing a few delvac cycles. and its only got 1k miles on the oil so I don’t wont to change it right now and i wont to do a sea foam treatment to clean some carbon out of the motor. I had the plenum pan gasket leak and it sucked oil thorough the motor for how knows how long before i got it. Also its got 150k on it. When I pulled the intake manifold there was BAD carbon buildup on 3 of the intake ports its was dry and really gritty, you could rub your finger across it and the grit was come off but it was pretty thick and there was no way to clan it out with out removing the head.

So can i do a seafoam soak w\o changing the oil, It says you can add it to your oil and i would think that after a long drive it will all evaporate.

Ans any recommendations on a clean up product?

 

[Gary Allan]

Just use a can of throttle body cleaner ...spray it with the engine running (or not). It won't screw up your oil, IMHO ...but it may skew the results if you intend to do a used oil analysis ...so you may want to skip it if you intended to do one. Just wait for the next round on the 0w-40.

Add the Seafoam to the tank to clean up any residuals that may stick around on the plugs/combustion chambers and to clean up the intake valves.

Just my $0.02

 

[loudist]

Isn't the 1994 5.2 fuel injected?

If so then seafoam in the tank won't clean up the intake.
First, go to PepBoys and buy some 'Cool Car' calenders and make sure the coupons are in there around the month of June. Check for the 'buy 3 get 3 free' Mobil 1 coupon. That should save you about 14 bucks on oil.

That should take the sting out of changing the oil if needed.

Some seafoam will get into the oil past the rings.
How much is anyones guess.

If the car is running fine, wait until just before you are to change the oil (200 miles or so) and do the treatment. Drive for a couple of days and then do a second Seafoam treatment, drive for a day or so and then change the oil and filter.
The oil should darken up a bit after the treatments, so you will get some crankcase cleaning benefits as well.

BTW, the engine should be well warmed up to operating temp when doing the seafoam treatments.

 

[Gary Allan]

quote:

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If so then seafoam in the tank won't clean up the intake.

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No ..the seafoam is to clean up any residuals that the throttle body cleaner leaves behind in the combustion chamber. He's looking to clean the intake. Seafoam is expensive, throttle body cleaner is not. It will adaquately disolve and suspend the no combustion carboned material in his intake.

The Seafoam in the tank will, over the tankful, take care of anything else.

Aside from blowby vapor ..the intake is dry. Why spend all that money on Seafoam to clean it???

 

[bugman53]

Yes it is the 5.2 MPI. That motor has an aluminum intake manifold that is 2 pieces and a steel plate on the bottom that sits in the lifter valley so after a lot of heat cycles the steel and aluminum expand at different rates so the gasket fails and it sucks oil though the intake, and it coats everything and its all baked on. It looks like heavy carbon buildup, The manifold I bead blasted so its clean but the ports in the cylinder head are filthy. im sure the intake valves are too. On a side note it Runs Awesome. tons of power and does not burn a drop of oil. But in not happy with the way the heads looked. And it’s a pain to pull the heads and rebuild them.

And it also pulls some oil through the PCV valve any ideas on a catch can? I tried a fuel filter and it was working but its was a pain to take off and clean out every couple weeks.

Thanks for all the help!!

 

[aldive]

I have used Sea Foam through the intake for years with no problems. Its a great product.

Good luck ....

 

[tweeker43]

i would wait towards the end of your oci before adding to your crankcase. someone said 200 miles; i'd go with that.

i forgot to change the oil in my lawn tractor for a long time after adding seafoam, and it was extremely thin when i did.

 

[Gary Allan]

Jegs sells catch cans cheap enough. Any large chamber will work where you lower the velocity enough for the heavier oil dropplets to drop out. A oil/water seperator for air compressors will work as well.

Since your carbon build up is limited to the ports and points downstream, you can use something like Seafoam or FP to remove the stuff via fuel adds via the tank. The injectors should do the job for you ..albeit at a slow rate.

One knowledgible DC tech commented that he liked the DC batch fire (he was talking about a 4.0 that uses 3/2 cylinder injector triggers) allowed fuel puddling that was used to advantage. It was this puddling that allowed cleaning agents to dwell (albeit briefly) on the hot backside of the intake valves. This is also allegedly why Ford and DC use different nozzle patterns for there injectors. The Ford appearently is actually superior ..but DC gets more long term reliabilty out of theirs.

This last paragraph is just repeated rhetoric ..not knowledge...so take it FWIW. I do know that my 4.0 uses a batch fire system. That's confirmed in the FSM. They also went to the same system for the ignition in 2000. 3 jugs fire two cylinders at the same time. 3 crank pulses for the fuel ..3 cam pulses for the spark.