knocking sound from under car when driving

[nooshinjohn]

hi guys!

got a wierd problem for the group...

when i drive my 63 i get a knocking sound from the area of my right rear wheel well. i have been told this noise

is made by the mechanical fuel pump. the noise gets faster and louder when i accelerate and slows when taking my

foot from the gas. the noise is not rotational as it there even at a complete stop. any help would as always be

appreciated...

John <img src="http://forums.aaca.org/images/graemlins/confused.gif" alt="" />

[Guest imported_kbm]

I had a similar problem with my 64 Riviera. It turned out to be a bad resonator. The inside baffle came loose.

Just another idea.

kbm345

[JohnD1956]

Several years ago I remember reading on the ROA e mail list, a thread about the fuel line noise on the first generation Rivs. I can't remember the fix, but Just how loud is this knock you mention.

Have you thought about the harmonic balancer? It may need to be rebuilt.

JD

[michel88]

My '63 Riviera developed a knocking sound right after I had installed a new fuel pump. It knocks faster when the accelerator is depressed and sometimes stops when it is idling. One theory the mechanic had is a loose baffle in the gas tank that is knocking now that the new fuel pump has more pressure. I dont know if the gas tank has baffles but this could be possible. The knocking sound also sounds like it is coming from the right rear well area. I would like to find out what is causing this sound.

[Guest Riviera66]

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Several years ago I remember reading on the ROA e mail list, a thread about the fuel line noise on the first generation Rivs. I can't remember the fix, but Just how loud is this knock you mention.

JD </div></div>

This problem was dubbed "Riviera Rattle" by early Riviera owners ... and was covered numerous times in Riview Q&As, particularly in the early years of the ROA. If you've bought the ROA Riview CD or have back issues, the issues of Volume 4, #3, Volume 4, #5, Volume 9, #3, and Volume 10, #5 will all have some pertinence. The last one, Volume 10 #5 showed where Riv expert Leonard Scott traced the noise source to wear of the vapor return line against the trunk floor pan. There's a photo showing the exact rub spot in that issue. This problem only exists for 1st generation Rivieras... none of the later ones experience it.

Darwin Falk

1966-70 ROA Technical Advisor

[nooshinjohn]

thanks for the input...

the noise I speak of gets so loud that I want to let that little elf out of my car and leave him on the side of the road. It is causing headaches, mostly because its so damn annoying. I work at a Buick dealer and all my driveability guys can say is they have never seen such a problem in a combined 85 years of experience.

What was the solution for the troubles in the Riviews?

Again my thanks for any input for solving this dilemma...

John <img src="http://forums.aaca.org/images/graemlins/confused.gif" alt="" />

[Guest NorwegianRivRoy]

Hi!

I'd guess that You might NOT experience the same problem as I did...but I had a strange knocking from the mid front of my 1964 Riviera when I drove it home after I bought it. It turned out to be the exhaustpipes that where mounted to close to the frame (not original exhaust system), so that the pipes hit the frame!! Yes it's true. Anyway, good luck!

(please read my post concerning MSD distributors for Nailhead)

[Jim Cannon]

John-

If it really bothers you, you can disconnect the vapor return line on your Riviera. That is where the noise comes from. Instead of using a fuel filter with the 3rd nipple, get one that is for a non-A/C car. Plug off the end of the unused vapor return line, don't just leave it open.