strange rattle

[sn-95matt5-0]

alright i got a strange rattle that happens in the higher rpms. i really have no idea wat it is but i think it may be ping. i run stock timing and 93 gas. i've also noticed a drop in oil pressure within the last week(its down to the n on the stock gauge)


my fear is the motor is taking a poop on me before my build is through.

wat do you guys think about this?

 

[HISSIN50]

Matt, I'd back the timing down and see how it does.

And if that doesn't cut it: Pull the SPOUT and set the timing to 26*. DO NOT PUT THE SPOUT BACK IN!

Drive around and see how it does. If the noise abates, it was likely ping (your running at locked 26* is very conservative as far as spark advance goes).

Good luck.

 

[Dino Dino Bambino]

alright i got a strange rattle that happens in the higher rpms. i really have no idea wat it is but i think it may be ping. i run stock timing and 93 gas. i've also noticed a drop in oil pressure within the last week(its down to the n on the stock gauge)


my fear is the motor is taking a poop on me before my build is through.

wat do you guys think about this?

If you're positive about the base timing being at 10 degrees, you shouldn't be getting pinging on 93 octane gas. Verify that the timing is correct and if it isn't, get it back to 10 degrees.
I also suggest that you hook up a mechanical oil pressure gauge to the block and see if the oil pressure really IS low. If that turns out to be the case, it's likely that the rod bearings are on the way out.

 

[sn-95matt5-0]

i'll check the timing...i've tried before but i cant find the pointer. i've got a picture off the interntet that shows were it is but i cant find it on my car

i'm planning on installing a mechanical gauge soon i was just waiting till i got the motor almost done. i've been puttin all my spare cash into this motor.

 

[Zero_chance]

If you dont know where the pointer is or it was removed, etc then how do you know youre running stock timing? Point being made not to try and be a smartasss but just to make you think. Unless you bought that car new from a Ford dealership and have serviced it yourself ever since then you really dont know what the timing is at and it seems it could be a likely culprit here.

 

[sn-95matt5-0]

alright i ment to my knowledge it is at stock timing. i was trying to find out if anything else could be the problem. i have had the car for the past 3 years and always have serviced it myself and i've never had a problem with it. this just started happening here recently. i also thought this may have been the problem and to tell you the truth i still hope its the problem.

 

[toyman]

I would also check the HB to make sure it isn't going south. It can rattle at higher rpms if it is coming apart.

 

[sn-95matt5-0]

thanks toyman i appreciate it. i will check tomorrow

 

[Zero_chance]

A possibility about the balancer. Do you notice a rough idle / engine shake at idle? That is a telltale sign of a blown balancer (just like mine) and is often misdiagnosed as a misfire.

 

[sn-95matt5-0]

yes it idles a little rouogh...and i looked at my balancer and it has some rubber material sticking out of the back of it. when in park and i rev the engine to 4k there is no noise but on the road at the same rpm its extremely loud.

 

[rj95svt]

Change the HB!! A bad HB caused my bearing problems. If that thing wobbles enough it could possibly take out the timing pointer too.

I would look at a pro products balancer. Seco keeps the in stock and I think they have a removable weight and if thats true you could use that on your 351 with the 28oz weight.

 

[sn-95matt5-0]

dang i just bought a ford racing balancer for the 351. how much do the pro products balancers run because i can get a stock replacement from jegs for $64

 

[sn-95matt5-0]

i just ordered a ford replacement balancer and two guages(oil pressure and engine temp) from jegs so i should have them all on the car by next week,(balancer will be on asap,

i check everywhere around my balancer and i cant find a timing pointer, it may not be on there but the new balancer came with one so i will be positive on the timing here shortly also,

thank you for the quick replies guys you've helped me out alot

 

[rj95svt]

Well guys I met up with Matt this afternoon and took a little ride in his car to help him diagnose his noise and without any doubt he is experiencing detonation. I looked around and for some reason his timing pointer is missing but that wasn't a big surprise if you've read this thead.

Now then since he's not messed with the timing and it didn't do this before I'm thinking it's not going to be timing but it still is a possibility. He is gonna check it as soon as he gets his new balancer and timing pointer on to make sure. Since I'm thinking it's probably not going to be a timing problem what are some other things that could cause detonation on a stock engine?

I'm thinking that the problem is going to be fuel related. Either fuel pump, filter, dirty fuel injectors or possibly even a dirty maf. What do you guys think?

 

[sn-95matt5-0]

thanks again for meeting with me i really appreciate it.

i dont think its the fuel filter because i replaced it last fall when my iac went out and i was trouble shooting why my car kept dying on me.

i tried injector cleaner not too long ago and i also seafoamed the car lately...i may try and pour some of the remaining seafoam in the gas tank(i've heard that this works real well to clean the injectors)and see if that helps.

i will clean my maf tomorrow because now that i think of it, may most likely be it since i did install a pre oiled spectrum oil filter several months ago(before this started happening)

thanks again jarad

 

[Zero_chance]

Detonation could be because of excessive carbon buildup which retains heat from combustion and then causes the next charge of air and fuel to ignite.

 

[rj95svt]

How affective is the seafoam at removing the carbon buildup?

 

[Zero_chance]

Unfortunately I dont think there really is a definitive way to tell unless you pulled apart the motor, took note of the carbon buildup, put it back together, Seafoamed it and then pulled it back apart to see the difference. Im sure it does help but its hard to tell how much if any. Theres some carbon that just wont come off by that means. A lot of people think that its working because they get a huge cloud of smoke but an experience at my dealership kinda proves that wrong. My service manager gave the new kid keys to a car to run a similar treatment through the system by sucking it through the vac line. Turns out the keys he gave the kid were to an 07 Navigator that only had 6700 miles on it. That thing fogged out half of Massachusetts and theres no way a motor with 6700 miles had THAT much carbon. In any case if all else fails and this car isnt your daily driver, you could tear down the motor over the winter and clean the carbon yourself. Hell, why youre at it throw in a 347. How many miles are on the car again? DOnt remember if you posted that. It sucks that youre missing the timing pointer because it always is good just to recheck that the timing is in fact right. Have you switched gas brands or octanes lately? You could alwasy try going to Wal Mart or a parts store and get that 103 octane booster or equivalent. Right after I boought my car I got some regular 87 octane on a hot summer day and the poor thing was pinging like you read about. Put ina bottle of the octane booster and half a tank of premium and it went away within 2 or 3 miles on the highway and Ive been using the same gas station, same octane ever since. Its always good to stick with one gas station. For example if you go to a station that no one ever uses premium and then you start pumping that into your tank, who knows what youre dredging up from the bottom of the tanks. I tend to stay away from the "mom and pop" places and the likes. I mean, who knows if youre even actually getting the premium gas that youre paying for.

 

[divit250r]

Have you tried cleaning the MAF? That seems to help a lot of people who are having drivability issues in general. Good luck!

Scott

 

[RAD]

What mid pipe you have? Stock? Maybe cats are clogged and you have too much back pressure, check your spark plugs also.
Just throwing some ideas.