Ford E450 Engine Knocking

[ArkRVHog]

This is a pretty new MH (Forester 2801) with about 11,000 miles and we are getting more and more engine knocking sounds. Is this anything to be concerned about or take into the shop? Engine runs just fine (no misses, same power as always) but the knocking is annoying particularly during acceleration. It does seem to back off a little once we've been running a couple of hours or more.

I've alternated Regular fuel and Extra fuel fill-ups trying to go from 86/87 octane to 88/89...but that really didn't make a difference.

Thanks for the input!

[emm-dee]

When you say it’s knocking is it a lower pitch sound like a piston slap/knock? When you say you’ve tried higher octane fuel does that mean the sound is a pre-detonation sound you can get from bad fuel or advanced ignition timing?

[Iwannacamp]

I would go to an automotive suppies store and get Seafoam fuel treatment. One bottle (16 oz ) for every 15 gals of estimated gas in the tank. Get on the highway and drive at least 50 miles. If that doesn't solve you issue i would find a reputable repair shop and have them check it. It could be a cheap repair.

[No-Fish]

Another question, does the knocking change w/ engine rpm? and if your RV is less than 5 yrs old , take it to a shop It should be under warranty. the Ford power train is cover for 5 yrs 60k miles.
2016 3011ds

[ArkRVHog]

Originally Posted by emm-dee

When you say it’s knocking is it a lower pitch sound like a piston slap/knock? When you say you’ve tried higher octane fuel does that mean the sound is a pre-detonation sound you can get from bad fuel or advanced ignition timing?

The knocking is that typical metallic "tinging" sound...typically when I am accelerating roughly between 30-60 mph. I've been though 15-20 tanks of gas (at least) so don't think it is just bad gas or it would have finally gone away, right?

Sounds like it is something I should get checked out based on the responses so far...thanks!

[aceinspp]

I would defiantly take it in. Being a 2018 should be covered under Ford. Sounds like a timing issue and fuel pre detonating causing a pinging sound which would sound like a knock. Later RJD

[emm-dee]

Originally Posted by ArkRVHog

The knocking is that typical metallic "tinging" sound...typically when I am accelerating roughly between 30-60 mph. I've been though 15-20 tanks of gas (at least) so don't think it is just bad gas or it would have finally gone away, right?

Sounds like it is something I should get checked out based on the responses so far...thanks!

I had the same problem with mine. I had taken the 450 to a dealer for oil change and had them look at it. They immediately said it was a bad pully bearing and they could get to it in three weeks. I thought they didn’t have a clue.

Then I remembered that my neighbor was the shop manager at a different Ford dealer in a small town. He came over to the house and listened to the noise. When he said it was a bad fan (serpentine) belt I thought he needed to go back to tech school. He must have seen the puzzled look and said he had seen it before and bring it to the shop the next day.

When I got to the shop the tech removed the belt and started the engine (you can do that for a very short time). All the noise disappeared. New belt installed and 3,000 miles later still no noise. I know it sounds crazy but it was explained to me that if a belt is slightly out of round or balance it sets up a vibration that causes the adjacent aluminum heat shields to rattle. As the belt heats up while driving it changes the vibration level, sometimes completely eliminating it.

A quick test is to start a cold engine and run at various RPMs to verify the noise. Then, remove the belt (access it from underneath the engine) and do the same thing. Be sure to only run a short time because of no water pump or alternator. If the noise goes away get a new belt.

If it doesn’t then I’m out of ideas and you’ll have to see a dealer.

[dalford]

Am I missing something? 2018 Ford E450? Take it to the dealer. I would have the first week..

[TitanMike]

Originally Posted by dalford

Am I missing something? 2018 Ford E450? Take it to the dealer. I would have the first week..

Around here you would have called for an appointment in the first week. THEN, they would have gotten it in this last week.

[emm-dee]

Originally Posted by TitanMike

Around here you would have called for an appointment in the first week. THEN, they would have gotten it in this last week.

Very few Ford dealers will work on a motor home. The closest to me that does is very difficult to work with. The small one in the next town will only do what can be done without using a lift...but they make and keep appointments.

[PenJoe]

Originally Posted by Iwannacamp

I would go to an automotive suppies store and get Seafoam fuel treatment. One bottle (16 oz ) for every 15 gals of estimated gas in the tank. Get on the highway and drive at least 50 miles. If that doesn't solve you issue i would find a reputable repair shop and have them check it. It could be a cheap repair.

A 2018 with 11K miles would still be under warranty. If it is a spark knock, you may get away with driving it 50 miles, but not if is a rod knock. It could well be a timing issue and it should be addressed under warranty via a Ford dealer.

[Philkaty]

I use " Marvels Mystery Oil " in all of my cars / RV / off road toys.

[AbdRahim]

Let us know what you find out. I had this last spring after sitting all winter. I put in a half tank of high octane gas and it went away. I have not heard it since.

[chilidogtx]

We are having the same problem.
2018 Forester 2501TS. E450 chassis.
We took a trip to Tuscon and back. On the way back, the pinging got worse under load.
Based on the posts above, belt or timing, I guess we're on our way to the Ford dealer.
... if we ever get our rig out of Camping World for other warranty issues.
I'll post back once we have a resolution.

[Wandering]

I’ve got the same issue I think. Mine is pretty light but when accelerating and not all the time.

Will be curious to see what others find.

[Gidyupgo]

Same as wandering describes. Same narrow rpm band and very light.

[Gidyupgo]

...... oh, and it's done it since day 1 2016 E450 .

[Fishtexx]

Originally Posted by Iwannacamp

I would go to an automotive suppies store and get Seafoam fuel treatment. One bottle (16 oz ) for every 15 gals of estimated gas in the tank. Get on the highway and drive at least 50 miles. If that doesn't solve you issue i would find a reputable repair shop and have them check it. It could be a cheap repair.

This may very well fix the problem. From what I am hearing from several of you with similar symptoms, it could be a carbon knock. A small piece of carbon will attach itself to a valve or someplace in the combustion chamber, super heat on compression stroke, and ignite the air/fuel mix inside that cylinder before the spark plug fires, causing pre-ignition/detonation. Believe it or not, back in the day I repaired many of these by pouring metered amounts of water down the intake while holding RPM's at 2k-3k. The resulting steam would dis-lodge and remove the little piece of carbon, eliminating the pre-ignition. Some techs would use transmission fluid getting the same results, but creating a lot of smoke. Sea Foam is the only common snake oil I ever recommend, and might work mixed with fuel. It can also be substituted for the water described above.GM used to make a product specifically for this purpose and very similar to Sea Foam called X-66. Really good stuff for engines with a lot of carbon build up. On engines with excessive carbon, I would load the engine with it enough to actually stall it, let it sit for a hour or two allowing the Sea Foam or X-66 to work it's chemical magic, then restart engine. After restart, a vigorous test drive ensued. Don't lug those gas motors, let 'em eat!

[Iwannacamp]

Originally Posted by Fishtexx

This may very well fix the problem. From what I am hearing from several of you with similar symptoms, it could be a carbon knock. A small piece of carbon will attach itself to a valve or someplace in the combustion chamber, super heat on compression stroke, and ignite the air/fuel mix inside that cylinder before the spark plug fires, causing pre-ignition/detonation. Believe it or not, back in the day I repaired many of these by pouring metered amounts of water down the intake while holding RPM's at 2k-3k. The resulting steam would dis-lodge and remove the little piece of carbon, eliminating the pre-ignition. Some techs would use transmission fluid getting the same results, but creating a lot of smoke. Sea Foam is the only common snake oil I ever recommend, and might work mixed with fuel. It can also be substituted for the water described above.GM used to make a product specifically for this purpose and very similar to Sea Foam called X-66. Really good stuff for engines with a lot of carbon build up. On engines with excessive carbon, I would load the engine with it enough to actually stall it, let it sit for a hour or two allowing the Sea Foam or X-66 to work it's chemical magic, then restart engine. After restart, a vigorous test drive ensued. Don't lug those gas motors, let 'em eat!

This was my thought. 11K is low miles to have carbon deposits, but it's a cheap check and won't hurt a thing.

FWIW Seafoam is an excellent product. I keep it around all the time. It does exactly what it proclaims.....well I guess it does more. I have seen many cars fixed with a bottle of this stuff.

[chilidogtx]

Well, I had a friend recommend Lucas Fuel treatment so I've used it in every second or third tank.
I may try the Seafoam while I set up the appointment at a Ford dealer.
Thanks for the suggestions. I'll keep you posted.