• Hi Guest!
    If you appreciate British Car Forum and our 25 years of supporting British car enthusiasts with technical and anicdotal information, collected from our thousands of great members, please support us with a low-cost subscription. You can become a supporting member for less than the dues of most car clubs.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

BJ8 Idling very rough w/ odd sound - Now w/ VIDEO!

Share this page

B

BrandonBJ8

Jedi Trainee
Offline
Hey everyone! I'll just get directly to the point. My BJ8 is idling very rough. The idle is really slow and it keeps dying. It will get to the point that the engine is cranking so slow that you think it will die but sometimes it just keeps going extremely slow. The other odd thing is a very unique sound when I push on the gas. It almost sounds like a hollow whining sound; kind of like air rushing through something that is hollow. As I accelerate, it sounds like a hollow supercharger whine with some lose parts. It's really hard to describe but I've never had it before. The oil levels are okay with no huge leaks. Any ideas on what could be wrong and what I could check?

Thanks!
-Brandon
 
Re: BJ8 Idling very rough w/ odd sound on accleration?

Brandon, my first thought is that a hose it off or broken. check your vaccum line between the intake manifold and the distributor. Also, on the BJ8, check the hose that is connected to the brake booster. (how's your brakes). /ubbthreads/images/graemlins/cheers.gif
Dave C.
 
Re: BJ8 Idling very rough w/ odd sound on accleration?

Brandon,
Is the starter slow to crank? My bout with this traced back to the battery switch being vey worn, which hobbled the entire electrical system (ignition included). I'd include this in your "checks of the obvious". Engine timing might also yield some clues.
 
Re: BJ8 Idling very rough w/ odd sound on acclerat

Vette - I'll check that line and see what I can find. My brakes seem fine, so I don't think it's related to the brake booster.

Kcolas - The stater is not really that slow to crank. I still will check it though. What's the easiest way to check the battery switch? The engine timing has been fine so I don't think it would all of a sudden be off after not having any problems.

Thanks to both for the help,
-Brandon
 
Re: BJ8 Idling very rough w/ odd sound on acclerat

Brandon your symtoms still make me think it is in the intake track. Check you carbs. see if one of the plungers on the top of a carb came loose. check for intake leaks. use a spray like WD-40 if you have too. If you carbs went out of adjustment either in idle speed or richness it will slow the engine down as you discribed. Does the exhaust look black or sooty. on the other hand if you have just a vaccum or intake leak that would introduce more air into the mixture and your engine would be alittle lean. No soot. If your distributor got loose and turned alittle it will slow the engine down if it got retarded. so check for leaks, broken pieces or wrong settings. /ubbthreads/images/graemlins/cheers.gif
 
Re: BJ8 Idling very rough w/ odd sound on acclerat

HI Brandon, I would suggest that you do a compression check on the engine, assuming this problem came up virtually out of the blue---Keoke.
 
Re: BJ8 Idling very rough w/ odd sound on acclerat

Brandon, did you happen to fidel with the timing fine adjustment knob on the side of the Distributor just before this condition started to show up. I don't know how familiar you are with it, but this knob was intended for very small incremental adjustment of the timing for times of varied gas quality and altitude location. It is marked A and R for direction to retard or advance the timing. Again, if your timing got retarded just alittle it would give you the slow idle speed condition you have mentioned. But of course this would not answer for the whoosing or winding noise you mentioned.
Dave C.
 
Re: BJ8 Idling very rough w/ odd sound on acclerat

Dave - I did not adjust the timing knob prior to this. However, you mentioned the exhaust symtopns. My exhaust is shooting out small black particles now. You can put your hand by it while at idle and it gets black spots all over it. I just made a video of the car and I will transfer it to the computer soon so you can hear/see everything. There are also a few new leaks below that have my concerned. One is from the transmission(leaking from the rear) and the other is closer to the front near the drivers side wheel.

Thanks,
-Brandon
 
Re: BJ8 Idling very rough w/ odd sound on acclerat

sorry Brandon, but I can't seem to run those movies. I'm sure it is on my end.
 
Re: BJ8 Idling very rough w/ odd sound on acclerat

Brandon, I couldn't open all the videos but the one I did open was the one with reving the engine. I know you said it was air but on my speakers it sounded like a bad water pump! What is the fluid on the floor? is it water or oil? Sarge
 
Re: BJ8 Idling very rough w/ odd sound on acclerat

Anyone else having this problem? If so, I can try and change them to a different format.

Thanks
-Brandon
 
Re: BJ8 Idling very rough w/ odd sound on acclerat

Sarge - The fluid on the floor by the front drivers wheel is clear. So that very well could be it! How can I check the water pump to see if its bad?

Thanks!
 
Re: BJ8 Idling very rough w/ odd sound on acclerat

First check the level in the radiator. If the level is low look to see where the fluid is coming from. If it is coming from the water pump that will pretty much tell you. Grab on to your fan blades and see if there is any wobble. There shouldn't be any. Depending on how tight the fan belt is, you may have to loosen it.
 
Re: BJ8 Idling very rough w/ odd sound on acclerat

The radiator is pretty full so I don' think it's leaking from there. The fan belt was very tight and didn't budge at all; same with the fan itself. Any other ideas?
 
Re: BJ8 Idling very rough w/ odd sound on acclerat

If the fan belt is too tight it could cause generator and pump wear. This wear may be causing the noise???? Have you tried an usig an auto stethescope to locate the sound?
 
Re: BJ8 Idling very rough w/ odd sound on acclerat

I haven't tried a stethescope yet. How lose does the fan belt need to be? Do you just adjust the two bolts(one above and one below) to loosen it?

Thanks
 
Re: BJ8 Idling very rough w/ odd sound on acclerat

Three bolts. Two on top on, one bottom of generator. I think (some may disagree) one inch each way from center with a slight tug. Hey anyone else, can the belt be removed to see if the noise goes away when the engine is on for a few seconds? Then it would tell you if the noise is in water pump and generator or internal in the engine.
Auto parts stores like Napa carry these stethescopes with long tubes to lay onto the engine without getting burned or loosing fingers.
 
Re: BJ8 Idling very rough w/ odd sound on acclerat

Brandon, I adjust my fan belt alittle tighter than some. But Have never had any trouble with generator bushings or water pump. I make my belt so that it will give approximately between 1/4" and 3/8" in the middle of the top span of the belt between the generator pully and the water pump pully. You adjust the belt by loosening the generator mounting points (bolts), and pulling on the generator to the outside of the engine bay until you've pulled tight the belt. then snug up the generator mounting bolts. The Whirling, Wynning noise could be from damaged bushings in the shaft of the generator or the water pump. If they are damaged, tightening the belt will do no good. The bushings will need replaced. By the way, usually damaged bushings will cause the shafts of the generator and water pump to become loose and whobble. Wiggle them when you get the belt losened. BUT! If the bushings have been damaged and started to sieze, they might be tightening up and that would put one heck of a load on the engine and would be a cause to slow the engines running speed down. This would account for you two symptons.
Dave C.
 
Back
Top