Installing a Federal Q

David Henry

PCS Member
Are there any modifications made to the underside of a roof that is recommended if you are installing a Federal Q? And any other install tips?
 
Are there any modifications made to the underside of a roof that is recommended if you are installing a Federal Q? And any other install tips?

Oh yeah. In my case when I added the Federal to my Lifeliner it had the additional roof supports in place from the factory allowing me to mount this beast. It will rip itself off your roof if there is not support.
 
Oh yeah. In my case when I added the Federal to my Lifeliner it had the additional roof supports in place from the factory allowing me to mount this beast. It will rip itself off your roof if there is not support.

EXACTLY as Richard stated....if your rig does not have the factory supports in place it is imperative that you put some in !!:eek:

Of the 4 ambulances that I own/have owned they ALL had the factory supports even if they were not being utilized at the time I acquired them.

What is the rig you are looking to mount a Q on David ?
 
You can mount it on the roof, if you first drop the headliner, and install a 3/16" thick piece of steel, and weld it to the windshield header, and to a roof support that would be mounted behind the windshield. The second support might be 16" or more from the windshield. The steel will need to be contoured to the roof, and be very close to the inside of the roof sheet metal. Once that is in place, you can drill the holes and mount the siren to the roof. This is exactly what the factory originally did, when they installed any large roof mounted siren. The purpose of the steel is to support the additional weight, and to keep the siren from tearing the metal of the roof. Generally speaking, the roof of most vehicles is about a 19 gauge of sheet metal, which isn't strong enough to handle the weight, or to support the twisting action of the siren motor.
 
just the wight of the Q ridding up there will distort the roof. your support will have to be agents the roof. they used a shim of the oil soaked card board to separate the panels and keep then tight.
 
To me, that doesn't look stron enough to support a "Q". If memory serves me correctly, they weigh somewhere around 60 - 65 lbs. That's a bunch for what you've got. Add the torque from winding it up, I'm almost positive you need more. Didn't mean to give you bad news, but bad news is much better than tearing hell out of something.
 
He can always add a larger piece underneath, and it would be held in place by the siren mounting bolts.
 
To me, that doesn't look stron enough to support a "Q". If memory serves me correctly, they weigh somewhere around 60 - 65 lbs. That's a bunch for what you've got. Add the torque from winding it up, I'm almost positive you need more. Didn't mean to give you bad news, but bad news is much better than tearing hell out of something.

Russell is close,when I installed my "Q" on the 72 it weighed in at 51.4#....I just checked the Federal site and it says the weight of NEW "Q" is 49.0#... I think you get more "metal" on the vintage ones then the new ones.;)
 
The trick here is to stop the flex of the heavy Q on the thin roof sheet metal. The plate under the roof will help and large washers under the Q will spread the load. The PSP switched from Caprices to Crown Vics in 1990 they still had the huge Federal strobe gum ball siren speaker light. Within two months the lights were pulling through the roofs. Ford supplied a retro brace kit for the recall required pulling headliner and installing a large cross brace that anchored on side roof rails. This ended the problem but cost Ford big $$$. The Ford brace was curved to follow the roof line side to side. My fully marked and lighted PSP 89 Caprice has the big light and shows no signs of looseness I have never looked above the headliner so don't know if Chevie used a brace.
 
the key is just the roof metal is not enough, this support shown will spread the weight out to the heavy structure and the roof it's self will not be holding the weight just the support. the trick is to get it centered on the support.
first thing to do is place the foot on it from under neath and see if your support is wide enough to mount it there. then decide were you want it, mark and drill the holes from inside to out. seen many a time were the roof was crossed measure and the siren was centered perfect on it. but when marked and drilled it only missed the support with two holes by half a hole. there for cutting the lip of the support and making it vary weak

but personal I think it's to big a boat anchor to use. but you guys that are hooked on them get in good. the nice part is that the B&M uses the same foot print. as do all the rest of the federal line up.
 
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