Crooked output transformer and weird glue.

A good day to you all.

This is my first post on the forum. Once I figure out how to upload images
can someone take a look and tell me if I have a problem? Thanks.

I bought a used amp from Long and Mcquade (major Canadian music store) and noticed that the output transformer is crooked. Is this going to cause problems? The amp sounds fine so far.

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If you have a host for the pictures, click on the IMG button.

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move the cursor between the two ][ and hit enter a few times.

go to the web site where your picture is hosted, some may have a means to copy the image link like photobucket. or just copy from the browser and paste it between the img with the brackets. you may see the URL= bla bla bla and brackets with img. delete everything before the pasted img and after the pasted img . not sure this will show up properly but I will do it as an example. Also if there is an picture shown, it is the back side of my Mark V combo for your reference what the OT should look like. I had to edit a few times, added extra spaces as the stuff in the blocks were doing something else
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should look like this once the extra stuff is deleted...

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Thanks for the assistance.

That should do it. Let me know if more pictures are necessary.

If I am not mistaken, I believe you are referring to the Filament transformer (PT) one closest to the power cord. It does look crooked. At a closer look at the picture, it almost appears that the mounting screws on the left side may have been loosened. They do not look flush to the mounting tabs. It is possible they were bent at time of installation. As long as the wires are undamaged internally doubt there is any issue unless the amp just is not working. The tension post looks a bit odd, does it have a mushroom head where it meets the transformer? Is the chassis bent in any way? The tension is placed on the steel laminations and they are robust. The bobbins or windings should not be affected as they are covered by the metal caps on each side of the transformer. As for the sloppy varnish goo, that is typical unless you have goo oozing out when it is operating. The end caps also also be sealed in place to prevent vibration. The head will get warm due to convective heating of the tubes and thermal energy dissipated in the transformer as the fan is not very efficient in thermal control. OT is on the right side of the amp when looking at the rear.

If you need to inspect internals, you have to loosen the tension bolt that is against the transformer before loosening the hanger screws that hole the chassis to the shell.

Thanks for a speedy response. I generally avoid forums because questions remain unanswered for long periods. This was helpful and timely.

I learned a lot from your response bandit. I have since tightened up the tension post, but due to the uneven filament transformer it supports it from an awkward angle. The head of the tension post is flat with some sort of soft looking material where it makes contact with the transformer.

The chassis looks good. I suspect the mounting screws could be tightened.

I would actually loosen the mushroom post and see if the transformer is loose without the support from the mushroom (I believe it s actually a rubber covered table foot inverted but could not resource that part so what ever it really is leave it at mushroom post as the rubber pad starts out with a rounded surface).

The PT should have 4 bent tabs on all 4 corners made of steel. I have seen many transformers in my day such that the tabs were not perfectly parallel to the mounting surface. Also it appears that one of the screws used to hold the PT to the chassis looks as if it may have been partially removed. I can see it poking out on the left just behind the Choke which is the smaller transformer in front of the PT.

Removing the Chassis from the Shell: Use caution as there is potential for stored electrical energy that may be lethal (500V dc).

I noticed the amp is missing the Rectifier tube. I normally leave all the power tubes in place and keep the expanded metal cage attached. For what you may need to do here it may be of best interest to remove the remaining power tubes (just keep the outer pair together and the inner pair separate from the outer so you know which ones match to what).

This may not be something you want to do but if there are loose bolts and screws you may need too. Leave the amp unplugged and move the stand by switch to on (this will help in draining most of the stored energy in the power caps and other electrolytic capacitors that are part of the DC supply. Still you should treat this as a live circuit since there may be potential in the large capacitors that could be dangerous (up to 500Vdc). You may also take the amp to a reputable service center (perhaps the place you bought the amp and see if they can secure the screws that appear to be loose).

The Transformer is secured to the chassis with nylon lock type nuts. (at least the 2012 model is). The nuts on the right side may be secure as the transformer is leaning from the left side. If all 4 screws are present great, if not, you may need to buy some replacement screws of the same size and locking nuts for the screws. Not exactly sure on the spec for the screw or nut since I never attempted to remove them. There are two accessible nuts on the side where the transformer is leaning but you need to remove the chassis from the shell to access them. The other two nuts are hidden under the circuit board and no need to do anything there. If the nuts are present but the screws are backed out, you can just tighten the screws while holding the nuts with a socket to prevent them from rotating.

Easy method to remove chassis:

To loosen the mushroom post (unless there is a better term) a 1/2 inch open end wrench placed on the jam nut and a 5/16 open end wrench on the square part of the post just below the mushroom. Keep the post from rotating with the 5/16 wrench and loosen the jam nut until it is free (clockwise). Once the jam nut is loose, rotate it with your fingers until it reaches the top, then loosen the post in the opposite direction, It should move into the shell. It is held in place with a T-nut and if the spurs are intact this will be an easy task. Best to do this with the face of the amp on a carpeted surface.

Once the mushroom is lowered enough (at least 1/2 inch ) you may proceed to loosen the chassis hanger screws. Do this with hand tools and not an electric screw driver to prevent getting burs or stripping out the Philips slot on the screw head. Just loosen them but do not remove. Stand the amp back onto its feet and remove the two front screws first. Hold the back of the chassis with one hand and remove one of the rear screws on one side. You may need to swap hands to do the other screw. Best to hold the chassis up with one hand as it will want to drop. The front of the amp will be held in place by the front plate as it will be sitting on a shelf as it were.

Once the screws are removed, let the chassis drop a little while holding it (this will provide clearance for the screws holding the handle in place.) Slide the chassis out just enough until you have access to the reverb cables. The amp chassis will rest on the side boards on the back (there is one on each side) Remove the reverb cables from the RCA jacks and continue to remove the chassis from the shell. If you removed the power tubes, you can set the amp down on the transformers. Inspect the interior for the two mounting nuts for the transformer, if they are present just tighten the screws, if not, you can replace them with new ones after you get them from your local hardware store. I would probably replace both screw and nut so you will have a set that meshes together. It could be a #8-32 or #10-32 or #10-24. Get something close and you should be fine. You may want to use lock-tight on the threads to prevent loosening due to vibrations. Reinsertion of the chassis into the shell is the reversal of the removal.

Trick to chassis install, once you get the reverb cables connected, white goes to the back of the amp closer to you, gray mounts towards the front. Slide the chassis in and hold it in place. Grab one of the metal straps and insert both front and back screw, no need to tighten them, just get them started by hand but keep them loose. This will allow you to free your hands to install the other side. You may need to lift up on the chassis to get them started. Start with the rear screw first as you can see when the screw meets with the floating square nut in the chassis. The front one should just drop into place.

Once all of the hanger screws are tight (not too tight, just snug enough to hold the amp in place), restore the mushroom height until it stops against the transformer and tighten the jam nut. Do not over do it with the post. Snug enough against the transformer. Keep in mind that this will all be heating up and cooling down (expansion and contraction will occur)