Does that "fan dinging" sound metallic in nature? IOW.. is the car detonating? Otherwise.. that's a nice vac reading and means the motor has good ring seal and is nice and healthy. How much timing do you have at idle to get that reading and what is the initial advance portion of the number?
Yes sounds metallic. Say you took a piece of vacuum hose a few feet long and let it hit the spinning fan. Only tapping the fan once or maybe twice. Not letting every blade smack the hose. That is how it sounds. I havent been able to pin point where it coming from because my head is part way in the car reaching for the key. Will need the Wife to help me.
So it happens only during the initial start up?.. or while it's running too? And ave you noticed any pinging sounds while accelerating? PS. and what about the timing numbers I asked about above?
Only during start up. Seems to occur when the engine fires and the starter is released. Doesnt do it every time. But enough to make me concerned about it. I had a starter come loose and was hit by the spinning fly wheel which detonated it into the bell housing. There was a piece stuck in there for years before it finally blew a small hole in the bell and fell out. Dont want that happening again.
My intial advance is 14*. Im running manifold vacuum and not sure where it is at idle with the vac advance connected. No pinging at all through the rpm range or under load.
hmmm.. maybe sounds like the bendix/gear return spring may be a bit sticky. Did this just start occurring after fooling about with the timing?
So, is that the max timing you could achieve before vac started declining?.. or did you try even more initial advance to see if the engine vac would go even higher?
No, I noticed it the before I drove the car for the first time. The starter was already on this motor. I believe it is fairly new. Looks like one of the parts that was replaced in an attempt to get the car running before selling it to me. It has sat for many years. I am thinking the same thing about the bendix sticking. I just need to be in a better vantage point to hear it and confirm where it is coming from.
I havent played with the vacuum since friday evening. I didnt have time. Im still going to do some work in that area.
I need to pull the breaker plate and see what weight it's workin on in there. If it's 10L, I will go higher. If it's 13L , I will leave alone. At 14* initial and a 10L weight, I will be at 34* total advance. I think 40* is as far as I should go with the engine based on what I have read. I should be at 9.2:1 compression ontnos stock 250. See, Ive been doing my homework, learned a lot....thanks for all the links. Jeff too, I read them all and found more on classicinlines.com
When I first got my car back in 2012, I had a similar "fan" noise, but only when it initially started or when I gave it a quick snap of the throttle. I did findout that my alternator belt was a bit slack, and it was going slack between the crank and the water pump pulleys, and the cogs would catch on the timing pointer. I tightened the belt and made sure the pointer was pushed back against the timing cover as best as I could get it. Just a thought, and something really easy to check! You may already know this, too, but if you are still running the 200 front pipe on your 250, the 200 pipe isn't tall enough, therefore it's pulling your exhaust up towards the body (I think you mentioned this before?). I had the opposite problem in my 4dr when I went from a 250 to a 200. I tried using straps to hold the exhaust up higher, and when I did, the exhaust was mounted too tight to the body and the resulting vibrations sounded a lot like your at-stop vibration.
I was looking at that pointer the other day. It is VERY close to the top of the damper pulley. The sound I hear really sounds like the fan dinging a belt. It can't hurt to check it out, it could be the source of all my mysterious sounds. Thanks for the heads up!
Did a little tinkering today, nothing major. The shroud wasnt looking like it would fit so I manuvered it into place. Then I couldnt get it out, so I bolted it in. The fan blades are super close on the upper right side. I am going to loosen the radiator bolts and scooch it over to help sith clearence. While I was in there I plucked the timing pointer with my finger. It make the same sound that Im hearing. I bent it up away from the pulley but now I cant see the mark on the damper. I am going to remove it, elongate the holes and put it back. I also cut about 3/8 off my FORD breather nut. Now my hood closes without hitting it. Still so much to do, time is running out!
Found a few small puddles of coolant under the car today. Both radiator hose are leaking at the radiator, no surprise. Found a leak at the temp sensor. Hoping that is it. I painted a new grill I had, much better than my old one. Finished putting the bumper on and also finished the shroud. Ran the engine and nothing hits, so Im good there. The ding ding at start up is definatley the starter. Also found the trans low on fluid, knew it had to be. Book calls for 8 qts and I only have 7 in it. Maybe grabbing at straws but could that have causes the other noise? Seems like I thought it was coming from trans when I heard it. Will know next time I drive it. Here is a good pic of the stance after the coil cut. Here is a pic with shroud and cut down breather nut
