Hitchcocks Forum

Hello everyone, from cold there is no noise, engine sounds fine, but 2 miles there is a VERY loud rattle (marble in tin can) sound and sounds not right at all. Plenty of oil getting to rockers and all is tight when cold, not checked when hot.. Tappets are set ok.
It's a 350 1991 Indian

Any suggestions or advice would be much appreacheated

I hope we are all making the best of this weather, a bit to hot for me though !
Kind regards
ROBERT

Hello ROBERT----------- could you be a bit more accurate as to the location of this noise ??

Loose valve seat?

A marble in a tin can sounds like pinging/ pinking, check the timing, try a higher octane petrol. If my Bullet pings, it sounds like a crate of empty beer bottles on a corrugated road.

I would pull the head off and check as Norm says it could be a valve seat .

------ The "2 miles" delay means there's a time factor involved ie Heat generation, so Either pinking OR Ex. valve seat is a possibility..Assuming you've NOT altered the timing, points or the plug, an air leak between the carb. and cyl. head would weaken the fuel/air charge and make it prone to pinking ( Pre-ignition), but the sound this makes can be controlled by varying the throttle usually....A loose valve seat will indeed give a LOUD CLATTER and be continuous....My guess is it's a seat and probably the exhaust as this is the hottest place in your engine.......PS}-----If you do remove the head don't expect the seat to be loose when you check it...Remember it needed some heat to loosen it in the first place.............. Besides, if it were to be THAT loose then the head itself could well be damaged and in need of re-building, profiling and re-seating...This = £££ !!, so let's hope it's not that, eh ??

Hello everyone, many thanks for the replies. I think it could be the valve seat also. But though I would get confirmation !
As stated it only becomes apparent when it becomes hot. The sound comes from the front rocker cover.
Will order the parts today.
Thanks again everyone
Kind regards
Robert

Check the rockers. I discovered that the iron journals had worn a lump on the top of the rocker spindle and this was causing the rocker to jam slightly and release with a clack. I linished off the lump and have had no further issues but will eventually replace the rocker with a aluminium/steel Samrat version.

Check the rockers. I discovered that the iron journals had worn a lump on the top of the rocker spindle and this was causing the rocker to jam slightly and release with a clack. I linished off the lump and have had no further issues but will eventually replace the rocker with a aluminium/steel Samrat version.

Hi guys-----Yes, that's also a very real possibility..... Having tried the SAMRAT Aluminium bodied option myself I wasn't at all happy with its' tendency for the top cap to distort, but did like the slim design of the rocker arm.......... So I fitted the rocker arm into the old Iron body, opening up the oil feed holes at the same time. ( Thanks GRUNDA !!)............................................................