SeaFoam Cleaning

[Desert Patina]

I have to admit that with the current state of my SVO, I can have a sort of a bahala na attitude towards my car. Or instead, perhaps its more of a love of putting myths to the test, as my children and I are enjoying reruns of Mythbusters on Amazon Prime.

So last week I decided to follow up the Tide + Citric Acid radiator flush (which really did clear out a lot of the rusty mud that accumulated in that engine) with a SeaFoam top-end cleaning.

The car always seemed to stumble at low revs, and recently started to stick at 2k rpms. Also there was a rattle that kept happening at high boost and rpm.

To fix this I've done quite a bit. I've replaced the TFI (as some call it, and its likely properly called), rotor, cap, wires, etc... I even wound up swapping out the distributor after rebuilding the old flat-top proved once again that my bane is crumbling plastic in this car as the washer/spacer that keeps the top rotor up came out while re-installing the drive gear). Still the rattle remained.

So I used a bit of the seafoam to clean out the Idle Control, and set it up as directed.

Now, at this point I should go give a bit of history. On the F-Body boards there is a long post about how to do a SeaFoam cleaning. Then about 27 pages into it someone shows up and claims its all hogwash. The procedure involved sucking seafoam cleaner through the brake booster line .... slowly. While doing it, expect lots of white smoke and perhaps a full smoke screen when trying to get onto the freeway. To make a long story short, that was too dangerous so Seafoam came up with a new plan. The Mopar abandoned their foaming combustion cleaner (the preferred option for those who hated the SeaFoam), and I am not really interested in joining Amway (sorry, Amsoil) just for a 9 dollar can of foaming cleaner, however superior that product seems to be.

So back with SeaFoam who nowadays have a little red tube that you stick into the intake right before the throttle body. Slip it under the intake hose, increase RPM by about 500-1000 over idle, and spray half the can in. Let it return to idle and shut off the car. Wait. Then drive aggressively. Expect extreme emissions. (I tell you I'm not putting it half as eloquently as they do in the directions). And nothing I do here should substutite for instructions. Its just my own clumsy little tale, nothing I did was elegant or prescribed at all.

So thats what I did. I slipped it on, but couldn't actually start the car. Too much vacuum leak around the hose going into the intake. So I plugged up that hole as best as I could.

Then when the car started I let it warm up, then upped the revs to about 1800 by putting something under the throttle and started spraying. The engine almost died, so I stopped, let the RPM's recover. Then sprayed again. After a while I could maintain the spray without worries. The smoke was coming out the exhaust.

When I got to about half way down the can, I removed the spacer on the throttle, then quickly dashed in to turn the engine off. Well, quick is how it felt, but it wasn't that quick.

Went in, enjoyed a bit of a morning with my kids and wife, and came out probably about 20-30 minutes later. I took off all the SeaFoam equipment and took it for a ride.

When I finally opened it up, I kept the car in control and looked back, I didn't see any smoke screen. Which is good, I did this all early in the morning on a Saturday to avoid any mean glares or potential lynch mobs after my junkyard SVO.

Now remember, this car had a severely compromised head gasket when I bought it. There was carbon buildup on the intake and in the head (which I had tried to clean off with b/12 gently with a rag).

But I can say the pinging decreased. Now when I drive it, the pinging is non-existant. But that isn't all.

The car started stalling after a bit of aggressive driving. It got so bad I pulled off the freeway, and it completely stalled at a left turn light. I waited for a bit and it started right up again.

However, that didn't seem to me to be a Seafoam induced problem, that sounded more like a TFI problem. I went home and replaced the new (cheap?) TFI with the old Motorcraft one and that seems to have fixed that problem. And I hope that is the problem because my 89 has been doing the same thing recently since I changed its timing belt.

And... the idle is steady now. There's still an intermittent stumble, but is much less frequent and the RPM doesn't seem to move when it happens. Oddly enough the idle was even better with the other TFI, but high RPM's is better with the new one.

So now my I'm dealing with a jumpy dipstick, and there's no bubbles in the radiator (I think, I might go double check that) and no cappachino in the oil. I'm thinking perhaps the Motorcraft PCV valve I got is not the super PCV that people tell me I need.

[MikeFleming]

Change the engine oil now that you've gotten it all dirtied with seafoam residue.

[Desert Patina]

Well, it is the right PCV valve. But half the time (in my search) people say it is worthless also?I wish I knew the part number for the Forced4 white check valves. Perhaps I'll go turbofordneck and put a brake booster check valve to help the PCV valve out.

[Desert Patina]

Strike that, the engine is still trying to cut out in aggressive driving, even with the motorcraft TFI...

What I'm seeing (and I have this on my 89 too) is that after revving it up to 4500, when I let my foot off the gas and the engine hits the bottom of the troff of rpm and would normally flatten or even increase RPM, it stalls momentarily. After a while it just starts stalling whenever it wants to.

If I don't drive above 4000rpm, I never see a bit of trouble.

The new distributor (from NAPA) didn't have a machined surface to install the TFI onto. It was rough and grey like a new cast-iron pan.

Also, since I was just moving the TFI, I used regular thermal compound from Radio Shack.

But perhaps I'm looking in the wrong place for the source of this problem?

[MikeFleming]

Two initial thoughts come to mine.

1) Related to high-RPM under little load: Bad valve spring(s) that is letting an HLA hold the valve open briefly.
This will take a few seconds to recover no matter the load (power).

2) Related to high load at any RPM: Not enough fuel flow.
This may recover immediately when load is reduced or take a few seconds depending on fuel flow and pressure.

Get that fuel pressure gauge back on there and if FP is OK, think about replacing the valve springs.

You mean cast aluminum pan? I don't recall ever seeing a cast iron pan (sump) on these engines.

Was there a boss & two screw holes to mount the TFI to?

[Desert Patina]

Thanks for the suggestions, I'll follow up on them.

One point of clarification, when I meant a cast-iron pan, I meant to say cast-iron skillet or dutch oven. It had that kind of grey rough surface.

Yes, there was a boss. I did install the TFI onto a surface that had two screws and matched the back of the TFI exactly, I even lost my TFI wrench doing it but that is another story. The old surface was machined smooth and shiney, the new one was flat and rough like it was simply cast.

At one point on Saturday, I was stranded and couldn't start because of the condition.

[MikeFleming]

T... I meant to say cast-iron skillet or dutch oven. It had that kind of grey rough surface. Ahhh. Like a corroded, acid-dipped, blasted surface?


At one point on Saturday, I was stranded and couldn't start because of the condition. So it cranked but did not start?

When cranking did it sound like no compression [in one or more holes] or more like out of fuel?

[Desert Patina]

Hmm, perhaps like an acid dipped, blasted surface. I've not seen one generally, but it fits what I would anticipate it would look like.

Unfortunately my thermodynamics fails me here. I understand that rough dull surfaces radiate heat better, but I do worry that it doesn't conduct heat better even with the thermal compound. The difference in conduction between rough and smooth surfaces through a colloid medium might have come up in my ME studies many years ago, but I have nothing ... only a mental vacuum on that topic now. My guess is that metal-to-metal is still much better, and thus more metal contact area the better, giving a big tip to the smooth surface. But I tend to over-worry my projects, and doubt if it made that much difference that NAPA would have cared enough to machine it.

As far as being stranded, I cranked it about every three minutes until it eventually started on its own. And even then it stalled a few times on the way home (but recovered before completely stopping).

When it didn't start, I did hear the fuel pumps and there was a roughness (but not a loping roughness?) to it that if I had to guess would say it had good compression.

Its always had a rough idle and sounds like it misses occasionally. But after all the ignition work I've done, I'm begining to believe the late owner probably put in a new cam. It has a trick camshaft pulley, which might also indicate he changed the cam.

thanks again, as always, for your help

[in2fords]

Is it a adjustable cam gear?

[Desert Patina]

Could you tell me how I would know, how they work?

It is a solid piece as far as I can see. But it has advance/retart marks at each cog as well as the main mark that you line it up with, which I think is more than the stock version came with.

Again, I might be wrong, my only reference is against my NA 89.

[in2fords]

Sounds like a non adjustable gear.
You need to go back to the basics, good tune up with quality parts, check gaps and timing light, if that is satisfactory then its time to check cam timing, fuel pressure, compression test, leak down test,ect.....
If those all check out then its time to go back to your sensors, I know you replaced the tfi, did you use the paste for the heat sink?

[MikeFleming]

Sounds like the Ford SVO Motorsport unit.

You have to pull it off he cam snout and re-position it on different slot. Has fixed settings of zero, and +/- 2, 4, 6, & 8 degrees. iirc. Each slot has it's own respective outer line-up pointer.

[Desert Patina]

Sounds like the Ford SVO Motorsport unit.

You have to pull it off he cam snout and re-position it on different slot. Has fixed settings of zero, and +/- 2, 4, 6, & 8 degrees. iirc. Each slot has it's own respective outer line-up pointer.

Yep that's the one.

[Desert Patina]

[...] I know you replaced the tfi, did you use the paste for the heat sink?

You must mean the thermal compound (I see some people calling it dielectric grease but that is a no-no http://www.tomshardware.com/forum/283905-31-dielectric-grease-thermal-paste ).

Why yes, I did.

http://www.svocop.com/forum/showthread.php?1565-SeaFoam-Cleaning&p=12801&viewfull=1#post12801

I about had to turn in my geek card though for not having any on hand when I needed it.

[18lbs]

Guys, as an aside to this initial thread, any known downside to using the Seafoam. I have been considering using it on my DD Explorer that has about 120,000 miles on it. A preventative tonic of sorts?

[Desert Patina]

Others might know more dangers, but here's the ones I read but can't confirm...


It might uncover or make hairline fractures worse in the combustion chamber
It might loosen up carbon bits that might knick your valves where they seal, and pepper your turbo blades
It might put a real load for your catalytic converter to catalyze
Smoke screens can really annoy your neighbors


There were some concerns with how people used to suck in seafoam through the vacuum lines, perhaps encouraging hydrolic lock. Also the can has a warning that you absolutely have to insert it into the intake airflow after the MAF sensor.

[Desert Patina]

I should also add that at BobTheOilGuy's forums their are a few camps that claim you can get the same effect (even better) using different techniques.

One came says a sprayer to mist a gallon of distilled water into your airtake is cheaper and easier on your car.

Another camp says that the Amsoil powerfoam does a better job of foaming up and getting to all of the areas of the intake and combustion chamber. And since it is foam you can spray it into a vacuum tube and it works better.

Yet another camps says that pouring a bit of b-12 or cleaner of your choice down the spark plug socket overnight (and manually turning the engine a few times right before bed and in the morning) works the best.

Another camp says that Techron based gas additives do the best job, and that the only real reason people get such carbon buildup is they don't drive fast and furious enough. I bet that camp throws wild parties.

[Mike S]

Your stumble after a 4k rev is either weak springs as mike suggest or weak lifters. You can tell if the lifters are suspect by checking if you get the same results by revving over 4K when the engine is full temp and when it is cold. If there is no difference, it is the springs. If there is a difference, then it most likely the lifters. I would would replace both if I was going to take it apart. You will also want to verify clearance and add shims as necessary.

[MikeFleming]

... and that the only real reason people get such carbon buildup is they don't drive fast and furious enough. I bet that camp throws wild parties. The last camp definitely has the hottest women at their parties.

Just sayin'.

[Mike Croke]

In the interest of science, if you get the crank-but-no-start situation again, try flooring the throttle pedal while cranking. I have heard two versions of why this can help with a flooded engine and both explanations remain urban myths as yet. The first reason to floor the pedal is to allow maximum air flow through the engine which will "dry" out a flooded engine. The second version is the computer recognizes the wide open throttle during cranking and does not fire the injectors.

With regards to heat transfer from the TFI module to the distributor body, heat will conduct through a solid at a higher rate than it will convect or radiate at a surface at real world operating temps. For reference, the CPUs in our PCs have a highly polished flat contact area between the chip and heat sink.

[MikeFleming]

The first reason to floor the pedal is to allow maximum air flow through the engine which will "dry" out a flooded engine. The second version is the computer recognizes the wide open throttle during cranking and does not fire the injectors. Actually both happen. When the throttle is open, more air is admitted (although past more than 15% or so does not allow more airflow as the throttle body opening is not the limiting flow factor at cranking speeds).

When WOT is detected during cranking, the EEC does indeed not spray any fuel. Almost all EFI systems do this.

Note that the TPS sensor and associated wiriuing must be in proper working order for the EEC to detect WOT conditions.

[Desert Patina]

Thanks for all your help.

There is good news... the dipstick hasn't popped out in a while. It hasn't been stuck at 2k for a while (though it can sometimes idle at 1500 on cold mornings it doesn't stay there). The pinging is gone, and I feel like I can drive it like a normal car. This past week was the first time I've ever forgotten I'm driving a fragile car and just drove it normally. I think that is all I can really hope to expect from a Seafoam cleaning, so I'm happy with that.

Also the cutting out isn't above 4k per se, it happens that ​after I take it to 4k it starts cutting out intermittently. It still does that, but with all the wiring that is exposed (etc...) it might as well just be a short that I need to find and tape.

So crossing my fingers, and perhaps a little electrical tape, I have a stable driving car for the next few months while I concentrate on other things. My other mustang is stabalized now that I changed the oil.

[Desert Patina]

Well that didn't last long.

Left stranded in the middle of an intersection. No spark (well occasionally there is a glimmer of a spark that lasts maybe a few revolutions and quits).

Time for my trusty friend, the cranks but won't start checklist.

le sigh...

[MikeFleming]

So it runs good only on odd-numbered days?

[Chalky]

So it runs good only on odd-numbered days?

.....every other month????