Yanmar Digital Exhaust Temperature Indicator | 150633-91348 YUASA M&B Marine Engine Digital Exhaust Thermometer, Ship Diesel Exhaust Temperature Gauge Spare Part

Product Overview

Built to the Yanmar-compatible OEM part number, this YUASA M&B instrument is the gauge that sits on the monitoring panel and tells the engineer what the exhaust gas is doing at that moment. A 304 stainless probe takes the place of the original sensor in the exhaust pipe, a metal braided cable carries the signal back to a compact display head, and the temperature appears as a number in the window instead of a needle position on a dial.

It is fitted wherever a Yanmar diesel is working: main engines on cargo ships, tankers and fishing vessels, and the auxiliary generators that carry electrical load in port and at anchor. Fleets hold one as a store item so a failed gauge does not become a wait-for-parts delay at the next port, and repair yards fit it during an overhaul when the original instrument has gone cloudy, sticky or simply stopped.

Day to day, that number is one of the quickest health checks on the engine. Exhaust temperature that climbs out of step with the load supports a restricted exhaust path, a turbocharger no longer delivering air, or cooling water that has stopped removing heat — and it shows up long before cylinder damage does. A Yanmar marine diesel exhaust temperature indicator also removes the angle-reading problem of a dial: the same figure faces whoever is standing at the panel, which matters when two people are comparing a reading from opposite sides of a dark engine room.

Key Features

• Threaded for the original Yanmar exhaust port. The thread follows the standard marine pipeline pattern used on Yanmar exhaust pipe bosses, so the probe goes straight into the port the old sensor came out of, with no adapter, no re-tapping and no pipe modification.
• Digital readout instead of a needle. A pointer-type ship engine exhaust temperature monitoring gauge asks you to judge an angle against a dim dial; the LCD gives a direct figure that stays legible in a poorly lit engine room and reads the same from any position.
• 304 stainless sensing end. The wetted probe is stainless steel selected for hot flue gas, so it resists the corrosion that eats through cheaper probes and keeps the sensing point intact across long running hours.
• Braided metal cable. The lead is sheathed in a metal braid that stands up to chafe against pipework, oil mist and radiant heat — the three conditions that normally end an instrument cable's life in an engine room.
• YUASA M&B sensing core. The chip that turns heat into a number decides whether a reading can be trusted. This one is built for stable conversion and a low failure rate, and it holds its signal against engine vibration and the electrical noise around a running diesel.
• One complete assembly. Display head, probe and braided cable arrive together as a set, so nothing has to be salvaged from the failed unit to complete the repair.

Specifications

Working Principle

The probe sits in the exhaust stream. Heat reaches its sensing element, the signal runs back along the braided cable to the display head, and the YUASA M&B chip converts it into a digital value that the LCD refreshes continuously. There is no Bourdon tube, no capillary and no pointer linkage to stiffen or drift, which is why a digital ship engine exhaust temperature monitoring gauge holds its accuracy over years of service instead of slowly losing agreement with the engine.

What that number is used for is diagnosis. Exhaust temperature is the clearest single sign of how a diesel is burning: it rises when the engine is overloaded, when carbon has narrowed the exhaust path, when the turbocharger is not delivering the air it should, or when the cooling system has stopped removing heat properly. Read as a trend rather than as one figure, it gives the engineer time to act before a hot cylinder or a burnt turbocharger turns a routine watch into a repair job.

That is also why the display belongs on the panel rather than on the machine. The reading is meant to be seen while the engine is running and while somebody is walking the floor, so an instrument that has to be reached, angled or squinted at simply does not get looked at as often as it should.

Application Scenarios

• Main engines on commercial vessels. Cargo ships, tankers and fishing vessels running Yanmar diesels use the gauge to watch exhaust temperature across the load range, so a fouled turbocharger or a restricted exhaust shows up on the panel instead of in a breakdown report.
• Auxiliary generators. The same instrument covers the shipboard Yanmar generator sets that carry electrical load in port and at anchor, where a slow temperature drift is easy to miss on a shared panel.
• Yachts and small working boats. Patrol boats, engineering workboats and larger yachts use it as a drop-in replacement when the original Yanmar gauge fails, keeping the console layout unchanged and the wiring route untouched.
• Ship repair yards and marine chandleries. Yards fit it during overhauls and chandleries keep it as a shelf spare, because a Yanmar marine diesel exhaust temperature indicator is the kind of item that can hold a vessel in port if nobody has one on the shelf.
• Offshore platform power units. Yanmar diesel power equipment on platforms uses the same probe-and-display arrangement in places where the reading has to be taken at a glance during a round.

Compatibility & Part-Number Matching

1. Start with the marking on the failed unit. Read the number stamped or printed on the old ship engine exhaust temperature monitoring gauge and compare it with the OEM number this replacement is built to; if the two agree, the fit is confirmed.
2. Confirm the engine it serves. The part is intended for Yanmar marine main engines and Yanmar auxiliary generators. A different engine make may use a different port thread or a different sensing arrangement, so check before assuming it will drop in.
3. Look at the port itself. The probe is threaded for the standard marine pipeline boss on Yanmar exhaust pipes; if the thread has been bushed, adapted or damaged by an earlier repair, that has to be put right first, because no new probe will seat properly in a damaged boss.
4. Measure the cable route from the exhaust pipe to the display position on the console or monitoring panel. The braided cable is supplied at standard length, so an unusually long or awkward run is worth raising before the order is placed.
5. If anything is unclear, send a photo of the old part, the engine nameplate and the panel position. We check it against the part number and tell you plainly whether this is the right replacement for your installation.

Installation & Maintenance

Two things decide how well this instrument ends up performing: the condition of the boss it screws into, and where the display head is placed. Before anything is fitted, the old probe comes out and the thread is cleaned back to bare metal and checked for damage from earlier repairs — a crossed or bushed boss will not give a gas-tight seat however carefully a new probe is turned in. The panel end is settled at the same time, because the display has to be visible from where the engineer actually stands on watch, not from wherever the cable happens to reach.

The work itself is short. A correct-size wrench, a thread sealant suited to exhaust temperature and a handful of cable clamps are enough, and most yards finish it inside a normal maintenance window — which is exactly why replacing a failed gauge is the cheaper answer than running without one until the next dry-docking. Nothing on the pipe run has to be modified, because the thread matches the original Yanmar exhaust port.

Where these installations go wrong is usually in the hurry: a probe tightened into a dirty thread, a cable pulled tight around a corner, a display fixed where a boot or a toolbox will catch it. Each of those shortens the working life of the part and, worse, makes the reading less trustworthy — and an untrustworthy gauge gets ignored, which defeats the whole purpose of fitting it.

Installation

1. Screw the stainless probe into the threaded port reserved for it on the engine exhaust pipe, and tighten it properly so no flue gas can escape past the thread. Check that it has started square before you apply final torque.
2. Route the metal braided cable along the pipe using the fixing clamps, keeping it clear of direct contact with the hot exhaust wall and away from any sharp metal edge that could cut into the braid.
3. Fix the display head on the engine console or monitoring panel in the position settled on beforehand, then push the cable plug fully home so vibration cannot work it loose.
4. Power on and test. The LCD shows the real-time exhaust temperature within about 3 seconds, and the figure should settle and hold rather than swing up and down.

Daily Maintenance

• Clean the probe thread. Carbon collects on the probe and around the thread; left alone it insulates the sensing point and the reading drifts. Clear it at each routine engine maintenance rather than waiting for a fault.
• Inspect the braid. Look for abrasion, flattened sections, or a braid rubbing on a sharp metal edge, and re-clip anything that has come loose before the strands start to break.
• Keep the display dry and readable. Water from washing down and heavy oil film both obscure the window; wipe it and check the housing is still seated properly on its mounting.
• Treat a jumping figure with suspicion. A reading that jumps rather than moves is usually a loose plug connection or an ageing probe, not a real change in exhaust temperature — check the connection first, then the probe.
• Hold a spare. A failed gauge takes the engine's temperature monitoring offline until a replacement arrives; as a marine engine spare parts supplier we see this most often during a port call, when there is no time left to wait for a delivery.

Acceptance Standard

1. Visual check. The set is complete — display head, temperature probe, heat-resistant cable and the original packing box — with no scratches, deformation or oxidation on the housing, the probe or the thread.
2. Part-number check. The marking on the product and the label on the carton agree with the OEM number this replacement is built to. That is the minimum any marine engine spare parts supplier should be able to show before a part goes into a ship's store, and it is what the receiving officer should sign against.
3. Temperature check. After installation the reading responds quickly and then holds steady, without the wild fluctuation that would point to a loose connection or a damaged probe.
4. Matching check. The thread seats fully into the Yanmar exhaust pipe interface with no gap and no leakage once tightened.
5. Packaging check. The carton carries the Japanese 補用 marking, consistent with the packaging used for original Japanese spare parts.

Ordering & Delivery

• Send the engine details with your enquiry. The engine model, the number on the old unit and, if possible, a photo of the marking let us confirm the match before anything is packed. That check is how a marine engine spare parts supplier should work, and it is why we ask for the marking rather than just the model name.
• Flag an unusual cable route. The braided cable is supplied at standard length; if the run from the exhaust pipe to the panel is longer than usual, tell us when you enquire and we will confirm what is possible for your order.
• Discuss packing for your store. Units travel in the original Japanese neutral carton printed 補用; if you need them labelled or repacked for a fleet store or a chandlery shelf, raise it with your sales contact.
• Confirm lead time, shipping terms and payment with your sales contact. These depend on quantity, destination and current stock, and are settled per order rather than assumed.
• Ask for the specification sheet. A copy of the specification is useful to attach to the vessel's maintenance file or to a survey submission; request it alongside your enquiry.
• Plan spares by engine type. Fleets and chandleries usually order one per engine or per vessel type rather than a single unit, so a failure does not take a gauge offline for a full delivery cycle.

Technical Support & Model Matching

Buying instrumentation for a vessel or a plant usually comes down to matching the part to the job. Our team at Jiangmen Jiexi Machinery Equipment Co., Ltd. has worked with buyers worldwide since 2013, and we start before the order: confirming the range, thread, connection and mounting you need, checking a model or part number against the equipment on site, and saying plainly where a standard unit stops and custom work begins. After delivery we stay reachable for installation, commissioning and fault-finding, with quality control that includes two extra testing steps beyond industry standard.

FAQ