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Heat  Sealing  Equipment  for  Mil-Spec &  Industrial  Bag  Packaging  Applications

Troubleshooting and Part # Information

Doughboy HS-B & BOSCH, SYNTEGON Doboy HS-BII Portable / Tabletop Sealers

Following are recommended tips for troubleshooting Doboy HS-B, SIG Doboy HS-BII, Bosch Doboy HS-BII, and SYNTEGON Doboy HS-BII problems.  You will also find a list of part numbers and descriptions for commonly used parts.

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Preventative Maintenance & Proper Use Tips*

Area of Machine

Advice / Technique

Heater Bar Cleaning

(Applies to HS-B and HS-BII)

HS-B Dirty Heater Bars

Dirty HS-B Heater Bar as

received from customer

HS-B Clean Heater Bars

Cleaned HS-B Heater Bar following

BaggingGuys' Ship-In Service

(Click photos for larger Detail Photo)

Over time, residue from your bags may build-up and burn on to your sealer's heater bars.  This is especially true if the interior poly surface of the package is exposed to the heater bars!  To minimize build-up on your heater bars, an easy and convenient methods of cleaning is as follows:

1) Heat-up machine to a temperature setting that is in the high-end of the adjustment range

2) Take a piece of cardboard (the back of an average writing tablet works perfectly) and feed it through the sealer, just like you would a bag or pouch.  As the cardboard passes through the heater bars, it essentially "squeegees" material off of the heater bar surfaces.

3) Repeat the process, either trimming the cardboard, or using different sides, until the cardboard passes through the machine clean, without picking up and bag residue.

If the gap between the heater bars becomes occluded (clogged) with burned-on residue, the bars will likely need to be removed, cleaned, and polished.  It is NOT recommended that the user attempt to remove the heater bars because replacing them properly is difficult and critical to proper sealer operation.  If this occurs, please contact BaggingGuys about our Ship-In Service for Doboy Portable Sealers!

Compression Roller Inspection

(Applies to HS-BII)

Photo of Broken HS-BII Belt Guides

Hardened Rubber on

Old HS-BII Compression Rollers

note Concave Shape in Center

Over time, the rubber on the HS-BII's Compression Rollers hardens due to constant exposure to heated bag material.  This hardening causes the center of the rollers' compression surface to become concave, resulting in reduced seal pressure at the center of the seal (see photo to left).

If you keep your Compression Rollers clean (see advice below) and you find that you need to repeatedly increase the seal pressure by turning in the pressure screw (or if your pressure screw is turned in all the way and you still cannot achieve a good seal), it's likely your Compression Rollers need to be replaced.

Frequency for Compression Roller replacement varies depending on frequency of use, seal temperature used, and frequency of cleaning.

Compression Roller Cleaning

(Applies to HS-B and HS-BII)

Regularly - with nothing sharper than a fingernail, remove any packaging material from both compression rollers on a regular basis.  Too much build-up on the rollers can cause the rollers to put uneven pressure on the bag, resulting in voids in the seal area.

On the HS-BII sealers, too much build-up can also cause the machine's frame to crack!

Interior Cleaning

(Applies to HS-B and HS-BII)

Use compressed air to regularly blow accumulated dust off of the exterior and out of the interior of the machine.

Belt Guide Inspection

(Applies to HS-BII)

Photo of Broken HS-BII Belt Guides

Scorched and Cracked

Belt Guide - due to older design

with no expansion slots.

Periodically, inspect the HS-BII sealer's brown, plastic carrier belt guides for signs of scorching (discoloration), warping, or cracking (see photo on left).  If any of these conditions are noted, replacement of both belt guides is recommended.

Newer HS-BIIs feature a shoulder screw that allows the belt guide to expand and contract independent of the aluminum belt guide stiffener.  Older HS-BIIs do not have this feature.  If you would like to add this option to your machine, let us know and we will quote the required parts.

Heater Bar Gap Adjustment:

(Applies to HS-B)

For most applications, the gap between the heater bars should be 0.025" (measured with a feeler gauge.)

Feeding Bags:

(Applies to HS-B and HS-BII)

If your pouches have a lip (i.e. one side is longer than the other - to make the pouch easier to open) when possible, try to insert your pouches into the sealer so that the exposed lip of the pouch is positioned above the top of the seal bars and compression roller.  If the lip, and inside of the pouch, is exposed to the heat and compression sections, the poly interior material will build-up faster on the heater bars and compression rollers.  If the exterior paper, foil, or barrier material is the only thing that is exposed directly to the sealer's working parts, the machine will stay cleaner longer.

If your heater bars do get dirty, CLICK HERE for details about keeping them clean!

Lubrication of Gears:

(Applies to HS-B and HS-BII)

The manufacturer recommends that you "1) Check Lubrication on a Monthly Basis or if sealer does not operate properly.  2) Brush a small amount of grease on the gear faces as necessary. and 3) Use Lubriko Hi Grease, or equivalent."  We caution you DO NOT over-lubricate!  Gears should have only a LIGHT COATING of grease on them.  While we offer the recommended Lubriko Hi Grease, any lithium-based grease suited to high-temperature use is useable.

Duty Cycle (How Long Will It Last?):

(Applies to HS-B and HS-BII)

Owners and prospective buyers of the HS-B and HS-BII sealers often ask: "Can I use this machine all day", or "We operate a 3-shift packaging department - will the HS-B (or HS-BII) work 3-shifts", or "We want to keep the machine hot all day and only switch the motor on when we need to seal.  Is that OK?"

For the HS-B series sealers our reply is - YES, to all three questions.

Regarding the life span of a Doboy sealer - These Doboy portable sealers are well engineered, durable sealing machines.  We have customers still using original HS-B design machines with late 1960s and early 1970s serial numbers.  The HS-BII design was introduced in 1994 and it has proven to be just as reliable as the HS-B design.  Plus, the HS-BII is even easier to maintain and service.

Some customers use these machines once or twice a month, others run the sealers around the clock.  With proper care, either design will make your sealing operation(s) more efficient for many years to come.

If you do use the HS-B or HS-BII over long periods, you can significantly reduce the mechanical wear and tear on the machine by turning off the motor when you are not actually sealing.  The HS-B series sealers are designed to be stopped in a fully-heated, "Pre-heat" condition until ready for use.  When you have packages to seal, simply switch the drive motor on, seal the packages, then switch the motor off (back into Pre-heat mode) until you are ready to seal again.

Of course, for safety reasons, all Doboy sealers should be shut-down (and unplugged if possible) when they will not be used for an extended period - e.g. when finished for the day, overnight, weekends, etc.

Important - If you also use a Doboy HS-C or HS-CII sealer, please see the Duty Cycle advice about those machines on this page (Click Here).

If properly cared for and given timely preventative maintenance, a Doboy portable / tabletop sealer can provide you with decades of reliable sealing capability!

How Much Current Does It Draw?:

(Applies to HS-B and HS-BII)

The standard Doboy HS-B and Bosch Doboy HS-BII sealers both operate on 115 Volt / Single Phase / 60 Hz (Standard, US Household) electrical power.

The HS-B (older styles) sealers draw 3.0 Amps.  The Power rating on the HS-B is 350 Watts.

The HS-BII (current machine styles) sealers draw 2.35 Amps.  The Power rating on the HS-BII is 270 Watts.

Sealer Feed Direction:

(Applies to HS-B and HS-BII)

How do I make my Doboy Tabletop Sealer (HS-B or HS-BII) feed in the opposite direction? - e.g. The bags currently feed from the LEFT to the RIGHT and I want them to feed from the RIGHT to the LEFT (or vice versa)?

Assuming you have your sealer mounted to either the standard C-clamp (which comes with all new sealers) or the Optional Cast Iron Base - All you really do is turn the sealer around.  Here's how:

On an HS-BII - Using a 3 mm Allen Wrench (assuming you have the original, button-head screws); Simply loosen the two screws on the side that attach the HS-BII to its C-clamp bracket (or, optional Cast Iron Base), remove the sealer from the bracket, tighten the screws you just loosened, loosen the corresponding screws on the opposite side, turn the machine around, hang it on the bracket again (the bracket should be oriented so the machine is safely hanging in the slotted holes), then tighten the screws to secure the HS-BII to the bracket and you’re back in business – but, going in the opposite direction.

On a Doboy HS-B - Using a large, flathead screwdriver (assuming you have the original, pan head screws); Simply loosen and remove the two screws on the side that attaches the sealer to its C-clamp  bracket (or optional Cast Iron Base), remove the sealer from the bracket, turn the machine around, reattach it to the bracket using the screws you removed from the other side (the bracket should be oriented so the machine is safely hanging in the slotted holes), then tighten the screws to secure the HS-B to the bracket and you’re back in business – but, going in the opposite direction.

General Sealer Set-up:

(Applies to HS-B and HS-BII)

Many Doboy machines we receive for service have been user-adjusted in a way that defeats the machine's ability to operate properly.  The sealer is designed to have a fixed side and a spring-loaded side - this applies to the heater bars and the belt/chain guides.  We will gladly try to talk you through proper set-up of your machine - Call us!

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Troubleshooting Tips & Tricks*

Problem Possible Cause & Solution

Does not seal or does not seal uniformly:

(Applies to HS-B and HS-BII)

1) Lack of Adequate / Uniform Heat:

1a) With the machine cold and the guards off, pre-heat the machine and check each heater bar as the machine heats to make sure both heater bars are getting hot, independently - it's possible that one of the heat elements (most likely the one on the side opposite the thermostat) is burned out.  If one bar does not get hot, there is either a loose connection or a bad heat element.

1b) If both elements are working, check the gap setting between the heater bars - it should be about 0.025" to 0.030" for most laminate bagging applications.  If the gap is too wide, it can prevent efficient heat transfer to the bag.

1c) Does this machine have a temperature gauge on it?  If so, what temperature is it displaying when you have the Temp knob turned up the whole way?  Is this temperature similar to what you have used in the past (or on your other sealers?)  If your thermostat is getting too old (typically 3-5 years old) it will sometimes prevent the elements from getting as hot as they originally did.

2) Lack of Adequate / Uniform Pressure - Check to make sure the compression rollers are clean and in contact with one another.  Try gradually turning in the pressure adjustment screw to add more pressure.  If the rollers are too old and hard, they can cease to exert proper pressure.  OR - If the rollers are (or have ever been) too dirty (i.e. lots of accumulated bag material clinging to them); It's possible you may have cracked your machine's frame.  If this happens, the frame spreads when the bag comes through the compression rollers and prevents them from exerting enough pressure on the bag.  If you have (or ever had) lots of build-up on the compression rollers - Look inside the machine, directly above the compression rollers and inspect the frame for a telltale crack in the bridge piece that connects the left and right sides of the sealer.

3) Seal Area Contamination - check bag for contamination (e.g. product residue, dust, grease, oil, etc.)

4) Poor Interior Coating of the Bag - this is a very unlikely cause, but a bag/pouch material with too little or no interior LDPE coating will not seal.  Discuss with your bag supplier.

PROBLEM: The Bodine V-10R Motor on my Doughboy HS-B Sealer Will Not Start

or Will Not Run.

(Applies to HS-B)

1) Bad Motor Switch - Check your motor On/Off switch to make sure power is being supplied to the motor when the switch is in the ON position.  If not, replace the switch (either a pushbutton switch on the end of the handle (call us for replacement details) or Part # 950644 (located on the top of the electrical enclosure), depending on the age of your machine.

2) Worn Motor Brushes - With the machine unplugged, carefully remove the motor brushes from each side of the motor.  A new brush measures about 3/4" OAL.  If your brushes are worn to less than 3/8", brush failure is a likely cause of your motor problems (or will be an imminent problem).  Replace the brushes (Part # 722-90243).

3) Motor Burned Out - If your switch is operable and your motor brushes are at least 3/8" OAL, it's likely that your motor is burned out.  Unfortunately, these Bodine motors are no longer available and cannot be repaired.  A Conversion Kit (Part # 457653) is available to replace the Bodine motor with a new Carter Motor (includes spacer plate, new motor mounting plate, and motor.)  This is a costly option, typically with a 4-6 week lead-time, but it is the only way to keep older model HS-series Doboy sealers running.  We offer rebuilt HS-B Sealers for slightly more than the cost of the Conversion Kit and your old machine may have trade-in value, depending on it's age, condition, and missing / present parts.  We also offer new Bosch Doboy HS-BII Sealers to replace your aging machine.

PROBLEM: Contact us with your problems.

(Applies to HS-B and HS-BII)

Contact us with your problems. We will post the solution here! Watch here for more solutions!

PROBLEM: I need service for my Doughboy Sealer or Doboy sealer.

(Applies to all portable Doboy / Doughboy Sealers)

If your Doughboy / Doboy sealer needs parts we can quote the parts.  However, unless you are an experienced mechanic who understands the operational principles of these sealers (e.g. why is there a fixed side and a spring-loaded side of the machine?) it's probably best you do not attempt to service these machines. 

BaggingGuys recommends you consider shipping your machine to us for repair evaluation and service.

Replacement and proper realignment of the power transmission and heating components on this sealer are critical and can be difficult if you do not have regular experience doing it.

* Machine troubleshooting & repairs should only be attempted by a qualified mechanic or electrician.  Power should always be disconnected prior to troubleshooting.

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Please see your factory instruction manual for additional troubleshooting tips.
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Common Replacement & Wear Parts (available at

Parts for HS-BII Series Machines
Spare Doboy Part # Description
* 335561 Carrier Belts
* 335578 Belt Guides
* 335594 Compression Roller (Left Side)
* 335601 Compression Roller (Right Side)
* 365809 Discharge (Drive) Pulley [Pulley with D-shaped Hole]
* 365808 Infeed (Idler) Pulley [Pulley with Bearing]
1 * 363563 Thermostat
1 * 341389 Heat Element
* 355041PM BaggingGuys' HS-BII Preventative Maintenance Spare Parts Kit
* 355041RBLD BaggingGuys' HS-BII Rebuild Spare Parts Kit
* 950644 Rocker Switch [Preheat / Off / Heat Motor] (DPDT)
  341388 Rocker Switch [On / Off] (SPST)
  273164 Grease for Gears
  371259 HS-BII Safety Guard (Right Side)
  371258 HS-BII Safety Guard (Left Side)

NOTE: A * in the "Spare" column denotes a part that is recommended as a common spare part for this machine. If a number is listed, that quantity is typically included in the New Machine Spare Parts Kit Option available when ordering a new machine. (Spare Parts Kit contents are subject to change without notice.)

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Parts for older HS-B Series Machines
Doboy Part # Description
894-10002 Thermostat
672-11500 Heat Element
722-90243 Motor Brush - for Bodine V10-R Motor
722-90247 Spring for Motor Brush - for Bodine V10-R Motor
722-00242 Bodine V10-R Motor - DISCONTINUED - See # 457653 Conversion Kit
457653 Motor (Carter Motor Conversion Kit - Replaces original Bodine Motor)
463912 Motor Brush - for Carter Motor
950006 Drive Gear (Large)
950012 Tension Arm
273164 Grease for Gears
951150 Safety Guard (Right Side)
951151 Safety Guard (Left Side)
539-00201 Blower Housing - DISCONTINUED - (Click here for replacement alternative)
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