4.0 SOHC Tapping noise w/video

[2000StreetRod]

Waste spark ignition system

Unfortunately, Ford implemented a waste spark ignition system on the second generation Explorer. That means one cylinder fires when on the compression stroke at the same time a paired cylinder fires on the exhaust stroke. The waste spark ignition simplifies (reduces cost) of the ignition system and slightly reduces pollution. Accordingly, I believe there are twice as many ignition pulses per revolution eliminating the distinction between top and bottom end using a strobe light.

It is extremely difficult to disassemble and reassemble an engine without disturbing dirt, carbon and sludge particles and getting them where they shouldn't be. Also, engine pre-lube will clog an oil filter in 30 minutes. I suggest that you immediately change your oil filter. Then I would drive the vehicle for a few hundred miles, flush the engine for five minutes, and then change the oil and filter again.

After that, if you still have the noise I would consider checking the valve lash adjusters which can be removed and installed without the special tool by removing and replacing the camshaft. The reason using the special valve spring compression tool is desireable is that the camshaft sprocket retaining bolt does not have to be loosened and the camshaft does not have to be retimed.

 

[BobWiersema]

Springs and Things

Unfortunately, Ford implemented a waste spark ignition system on the second generation Explorer. That means one cylinder fires when on the compression stroke at the same time a paired cylinder fires on the exhaust stroke. The waste spark ignition simplifies (reduces cost) of the ignition system and slightly reduces pollution. Accordingly, I believe there are twice as many ignition pulses per revolution eliminating the distinction between top and bottom end using a strobe light.

So that blows that idea.

After that, if you still have the noise I would consider checking the valve lash adjusters which can be removed and installed without the special tool by removing and replacing the camshaft. The reason using the special valve spring compression tool is desireable is that the camshaft sprocket retaining bolt does not have to be loosened and the camshaft does not have to be retimed.

Dale, If anyone could put together a spring compressor from things they find laying around the house, I think it would be you. If it was me, I would spend the 80 bucks on the tool just to avoid having to retime the cam. Plus I like tools.

Bob

 

[shelbygt]

It is extremely difficult to disassemble and reassemble an engine without disturbing dirt, carbon and sludge particles and getting them where they shouldn't be. Also, engine pre-lube will clog an oil filter in 30 minutes. I suggest that you immediately change your oil filter. Then I would drive the vehicle for a few hundred miles, flush the engine for five minutes, and then change the oil and filter again.

After that, if you still have the noise I would consider checking the valve lash adjusters which can be removed and installed without the special tool by removing and replacing the camshaft. The reason using the special valve spring compression tool is desireable is that the camshaft sprocket retaining bolt does not have to be loosened and the camshaft does not have to be retimed.

I know the machine shop used assembly lube on the cams, do you think that could clog a lash adjuster (lifters) and warrant changing the filter again after a week? If dirt or crap got into one of the lifters, I would still need to remove it and clean it. Other than the noise, will a weak or clogged lifter hurt anything? The shop did say the lifters were nasty when they pulled them apart with what looked like mud inside them when they bled them down.

I would feel better if I can see that everything up top is tight and not about to come apart from a loose bolt or something stupid like that, so I am going out to pull the valve cover now. Another weekend shot working on this thing!

 

[2000StreetRod]

replacing rockers & adjusters without special tools

Actually, I was going to mention later if the noise continues after a few hundred miles that the rockers and adjusters farthest from the camshaft sprocket can possibly be replaced without the special tool or retiming the camshaft. When the hydraulic tensioner is removed there is some slack in the chain. If all of the camshaft bearing caps are removed it may be possible to raise the end of the camshaft farthest from the sprocket enough to replace several of the rockers and adjusters. I plan to try it today when I retime the left camshaft.

 

[2000StreetRod]

Replace oil filter after 30 minutes

I know the machine shop used assembly lube on the cams, do you think that could clog a lash adjuster (lifters) and warrant changing the filter again after a week? If dirt or crap got into one of the lifters, I would still need to remove it and clean it. Other than the noise, will a weak or clogged lifter hurt anything? The shop did say the lifters were nasty when they pulled them apart with what looked like mud inside them when they bled them down.

I would feel better if I can see that everything up top is tight and not about to come apart from a loose bolt or something stupid like that, so I am going out to pull the valve cover now. Another weekend shot working on this thing!

My GM 60 degree V6 engine rebuilding book suggests the following:
Upon engine start run the engine at moderate RPM for 30 minutes to allow parts to seat
After 30 minutes replace the oil filter which is typically partially clogged with pre-lube

I doubt that pre-lube would clog an adjuster. It can accumulate in a quality filter and restrict flow. When the filter is clogged enough it gets bypassed allowing particles to circulate thru the engine.

Be confident in your work. I suggest that at this point you just replace the filter. If you want to do more then add engine flush, run the engine for five minutes and then replace filter and oil.

 

[shelbygt]

My GM 60 degree V6 engine rebuilding book suggests the following:
Upon engine start run the engine at moderate RPM for 30 minutes to allow parts to seat
After 30 minutes replace the oil filter which is typically partially clogged with pre-lube

I doubt that pre-lube would clog an adjuster. It can accumulate in a quality filter and restrict flow. When the filter is clogged enough it gets bypassed allowing particles to circulate thru the engine.

Be confident in your work. I suggest that at this point you just replace the filter. If you want to do more then add engine flush, run the engine for five minutes and then replace filter and oil.

I did run it for about 15-20 minutes and changed the filter and oil last week at initial start up, but I see what you are saying.
So I should just use an STP engine flush, or Marvels Mystery Oil and run it for 5 minutes then replace filter and oil? After I remove the valve cover and check for loose rockers, I will do this before removing the cams and adjusters.
It should only take about 30 minutes to remove the valve cover (I have lots of experience)

http://www.autozone.com/autozone/catalog/accessories/accProductDetails.jsp?counter=17&categoryDisplayName=Chemicals&fromString=&itemIdentifier=523555_0_0_&productId=523555&sortType=&parentId=17-10&filterByKeyWord=&categoryNValue=&navValue=101099&fromWhere=&itemId=1099-10&displayName=Engine+Additive+and+Cleaner&store=2478&skuDisplayName=32+oz.+motor+flush&brandName=Gunk

 

[BobWiersema]

Lifters

The shop did say the lifters were nasty when they pulled them apart with what looked like mud inside them when they bled them down.

You got to be kidding, the guy thought they were bad and didn't test any. Any kind of quality shop would have the equipment to do a leak down test on the lifters. Was this the same guy that didn't see the hole in head? I would think you could rig up something to push the valves down to pull the followers. At least the weather looks nice for you today.

Also, did he put those lifters back in the head bled down (empty, collapsed, no oil)?

New lifter are filled with test fluid to prevent damage at start up. If he put them in empty that could cause damage, especially on a older part like that.
You may as well replace all 12, sounds like about half of them got trashed.

Bob


A little something from some engine builder guy, I dont know where I found this.


Before installing lifters into the cam tower, they should be “primed” by hand to assure they are full of oil.

This is accomplished by holding the lifter under oil with the oil bore facing up, and depressing the piston several times.

If the lifter is functioning properly, you will begin to feel the lifter piston become stiff as the Internal chamber fills with oil. If after several depressions of the piston, you do not feel it become firm, then the lifter should Be replaced. The theory of the lifters is based on fluid dynamics. A liquid can not be compressed, Therefore, as the lifter become filled with oil instead of air, it becomes difficult to “squeeze” the viscous oil Out of the small oil bore.

 

[BobWiersema]

So I should just use an STP engine flush, or Marvels Mystery Oil and run it for 5 minutes then replace filter and oil?

Here is a cheap idea, try this, dump out a little oil and put a bottle of Rislone Engine Treatment in it and drive it around for a while. I have had some unbelievable great success with this stuff fixing lifter noise.

Start with something cheap, could be just a sticky lifter, and this stuff is great at fixing it.

Now I dont want to here anyone saying "oh, that stuff is crap" unless you have used it as many times as I have to fix this exact problem on a high mileage engine.


Bob

 

[RickOTR]

Those lifters are know to go bad in the SOHC engine. They are the same lifter sand cam followers that Ford puts in the 4.6 SOHC. I've replaced three of them on my Explorer already and mine sounded just like yours. You also need to bleed them before you start the engine. To do this, put the lifter in a can of oil and push in and out on the plunger, kind of like bleeding a master cylinder.

 

[shelbygt]

You got to be kidding, the guy thought they were bad and didn't test any. Any kind of quality shop would have the equipment to do a leak down test on the lifters. Was this the same guy that didn't see the hole in head? I would think you could rig up something to push the valves down to pull the followers. At least the weather looks nice for you today.

Also, did he put those lifters back in the head bled down (empty, collapsed, no oil)?

New lifter are filled with test fluid to prevent damage at start up. If he put them in empty that could cause damage, especially on a older part like that.
You may as well replace all 12, sounds like about half of them got trashed.

Bob

Yeah same place.... he said the lifters were full of milky, muddy looking oil/coolant. They were silent before this all began. I hope it is just a lifter sticking, as that is what it sounds like with the frequency of the tapping.
I am heading to the parts store to get the engine flush, filter and oil and see if that works. I just noticed that the 1 year old Ford thermostat housing is leaking AGAIN (great design!), so I will try and fix that when I remove the valve cover at the same time, since I will have to drain the coolant for that as well.

 

[shelbygt]

I have a bottle of Seafoam that I was going to use in the intake system until I was told that is not a good idea, but how about in the oil?? It claims to free sticking lifters.

 

[2000StreetRod]

Don't drive with flush or SeaFoam

I would not drive my vehicle with engine flush (I use Gunk and they tell you not to drive with it) or SeaFoam in my engine. It thins the oil and reduces protection of the bearings under load.

Today I tried to remove the rockers after removing all of the camshaft bearing caps. The only ones I could remove were the two farthest from the sprocket. The bearing next to the sprocket is a thrust bearing and prevents the camshaft from being raised more than 1/8 inch at the opposite end. To replace the other rockers or adjusters you will have to disconnect the sprocket and then retime the camshaft after the replacement.

 

[shelbygt]

I would not drive my vehicle with engine flush (I use Gunk and they tell you not to drive with it) or SeaFoam in my engine. It thins the oil and reduces protection of the bearings under load.

Today I tried to remove the rockers after removing all of the camshaft bearing caps. The only ones I could remove were the two farthest from the sprocket. The bearing next to the sprocket is a thrust bearing and prevents the camshaft from being raised more than 1/8 inch at the opposite end. To replace the other rockers or adjusters you will have to disconnect the sprocket and then retime the camshaft after the replacement.

Okay Dale,
That's not a big deal since I have the timing tools.

I bought the stuff Bob recommended (Rislone Engine Treatment) and as soon as the engine cools, I am removing and replacing the oil filter and putting a quart of that in and see if it helps after driving a few days. If not, plan "B" Pull the cam off and check the adjusters and possibly replace.

 

[BobWiersema]

Drugs for your Oil?

Okay Dale,
That's not a big deal since I have the timing tools.

I bought the stuff Bob recommended (Rislone Engine Treatment) and as soon as the engine cools, I am removing and replacing the oil filter and putting a quart of that in and see if it helps after driving a few days. If not, plan "B" Pull the cam off and check the adjusters and possibly replace.

Yea. Go Rislone, but read the destruction's, I dont think you should keep it in too long. The only stuff that you can run for a while is the Auto-Rx but that is more for sludge clean up. If the Rislone is able to fix it the results will be quick. Last time I used it was in a boat with a GM V6, we ran it around the lake putting a good load on the engine and that cleared it up. I hope you have the same results.

Bob

 

[Jakee]

I believe the other reason engines shouldn't be drove with any type of engine cleaner in it is so the gunk being dropped to the pan doesn't find its way to the oil pick-up screen. When this clogs, the oil pressure drops, and it's possible the only fix is to drop the pan and clean the filter. The chance is there and I don't see it being any fun to drop the SOHC pan with the engine in the vehicle.

I hate always being the negative "drama" type following these threads but the possibility is there. (it's happened to me) Just don’t put any load on the engine with cleaner in it and you should be okay.

 

[shelbygt]

I believe the other reason engines shouldn't be drove with any type of engine cleaner in it is so the gunk being dropped to the pan doesn't find its way to the oil pick-up screen. When this clogs, the oil pressure drops, and it's possible the only fix is to drop the pan and clean the filter. The chance is there and I don't see it being any fun to drop the SOHC pan with the engine in the vehicle.

I hate always being the negative "drama" type following these threads but the possibility is there. (it's happened to me) Just don’t put any load on the engine with cleaner in it and you should be okay.

I read some of the warnings about this stuff, but since my motor is pretty clean having it 90% broke down, there is no sludge or much of anything to clog the pickup screen, so I am not too concerned about that.

The instructions say to use it as a supplement to the oil and nothing about draining it, so a few days of driving should be perfectly fine IMO. I am sure if it is going to clear up the problem, it will do it sooner than later.

 

[shelbygt]

I let it idle for about 10 minutes and took it for a quick 5 minute drive taking it up to 5k RPMs and it made no change in the tapping. The tapping seems to be in sync with one of the injectors if I put a screwdriver against it and my ear. Here is another video of the noise.

http://www.youtube.com/watch?v=SyLGIsJbra8

 

[BobWiersema]

Anything New?

Any updates? Its been a couple days, has the Rislone done anything for you?

Bob

 

[shelbygt]

Bob,
We've put about 75 miles on it and no change yet. I drove it by the machine shop and he said it sounds like a lifter. He said put a couple hundred miles on it and see if the oil treatment clears it up before replacing the lifters. Unless it gets worse before then.
Thanks for checking up..

 

[shelbygt]

Found the source of the tapping.

I removed the cam and when I was taking the caps off, I noticed that one of the tabs that bolts that bar, (I guess it is an oiler for the cam) to the cap was broken. I looked at the bar and it is bent and has marks on it from hitting 2 of the lobes of the camshaft.
I may have bent and broke the tab when hauling the head back from the machine shoop, but I really don't know when it got bent. I am pissed that I missed it!

I am going to spot weld the tab back on to the bar and put it all back together and take the lifters back... 60 bucks is 60 bucks!

For some reason I can not get the back tensioner off. I torqued it to spec 49 ft lbs, but even using a breaker bar and long extension and tried an impact gun through the wheelhouse... it will not budge it. I hope I can get the rear chain sprocket back on with the tensioner still on. I might try heating it if I can't get the sprocket back on the cam.