Mark V reverb question

[chumbucket]

I picked up a used Mark V head recently and noticed that the reverb doesn't seem wet enough. I only really want to run reverb on channel 1 so I have the knob turned up full and hear the trail at the end but I hear too much dry signal. All 3 channels are like that. If I compared it to my Lone Star Classic, it seems like Mark V reverb is in the ballpark of 25-33% as wet as the Lone Star's reverb cranked up full. In fact I usually only turn the LS reverb up to around 9-10:00 on it's dial.
Does it sound like something is wrong?

Thanks

 

[Monstercastle]

Try replacing V4 & V5 tubes. They are the reverb send/return respectively.

 

[jdgebha]

I actually can't hear mine either even with a fresh set of tubes. I haven't really tried messing with it much tho but it hardly seems noticable.

 

[IronSean]

There's a JFet in the reverb circuit that's been prone to failure. Especially on older Mark V models (I think they replaced it with a more robust one in production at some point). Have a tech take a look at it if tubes don't help and it's not audible.

 

[Lef T]

If you are running in Tweed mode on Channel 1 you will not get reverb.
It is designed that way.
If you are running in Crunch on Channel two you will also have to bring the reverb up to match the other
channels.
Sounds like you have a problem though.