Stainless Steel Exhaust Elbow – Fits Yanmar 3JH2/4JH2 Series (Replaces 129470-13550)
Stainless Steel Exhaust Elbow – Fits Yanmar 3JH2/4JH2 Series (Replaces 129470-13550) is backordered and will ship as soon as it is back in stock.
Worry-free returns
Worry-free returns
Shop with confidence. If you’re not completely satisfied, eligible items may be returned within the return window, provided they are unused and in original packaging.
If the return is due to our error or a defective item, we’ll make it right.
Please contact us before returning any item.
Delivery and Shipping
Delivery and Shipping
Orders are typically processed within 1–2 business days.
U.S. orders usually arrive within 6–15 days, depending on stock location and destination.
International delivery times may vary due to customs processing.
Tracking information will be provided once your order ships.
Stainless Steel Exhaust Elbow – Fits Yanmar 3JH2/4JH2 Series (Replaces 129470-13550) is backordered and will ship as soon as it is back in stock.
Product Details
This high-grade Stainless Steel Exhaust Elbow is engineered for a direct fit on Yanmar 3JH2 and 4JH2 series marine diesel engines. It serves as a crucial component in the exhaust system, mixing exhaust gases with cooling water to safely discharge them overboard. Constructed from corrosion-resistant 316 stainless steel, it offers superior longevity compared to OEM cast iron parts.
This component provides a direct replacement for Yanmar part number 129470-13550 and interchanges with HDI Marine part JH2.
- Designed for a direct-fit, flange-mount installation.
- Built for use in marine diesel engine environments.
- Includes a new gasket for a complete installation.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Yanmar | 129470-13550 |
| HDI Marine | JH2 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
| Brand | Model | Stroke | OEM Part No. | Notes |
|---|---|---|---|---|
| Yanmar | 3JH2BE | 4-Stroke | 129470-13550 | Diesel |
| Yanmar | 3JH2CE | 4-Stroke | 129470-13550 | Diesel |
| Yanmar | 3JH2E | 4-Stroke | 129470-13550 | Diesel |
| Yanmar | 4JH2CE | 4-Stroke | 129470-13550 | Diesel |
Technical Specs
- Product Type
- Exhaust Elbow/Mixing Elbow
- Installation
- Direct-fit replacement
- Fuel Type
- Diesel
- Connection
- Flange Mount
- Housing Material
- Stainless Steel (INOX/316 grade)
- Housing Color
- Silver/Metal
- Dimensions
- 27.0 cm × 11.0 cm × 27.0 cm (L×W×H)
- Weight
- 1.25 kg (2.76 lb)
- Fitting Type
- Flange mount with bolt holes
- Inlet Size
- 1" (25.4 mm)
- Outlet Size
- 2" (50.8 mm)
- Warranty
- 3 years
- Construction
- Investment cast using lost wax technique
- Flange Thickness
- 8.2 mm (HDI version)
- Tube Thickness
- 2.5 mm (HDI version)
What’s in the Box
- 1 x Stainless Steel Exhaust Elbow
- 1 x Gasket
Installation Notes
- Ensure the engine is completely cool and disconnect the battery. Close the raw water seacock.
- Place a drain pan under the old elbow to catch any residual coolant or water.
- Carefully disconnect the exhaust hose and raw water inlet hose from the existing elbow.
- Unbolt the old elbow from the exhaust manifold. You may need to use penetrating oil if the bolts are seized.
- Clean the manifold mating surface thoroughly, removing all old gasket material and corrosion.
- Position the new gasket on the manifold, aligning the bolt holes.
- Install the new stainless steel elbow, ensuring it sits flush against the gasket.
- Thread the mounting bolts by hand first, then tighten them evenly in a star pattern to the manufacturer's torque specifications.
- Reconnect the raw water inlet and exhaust outlet hoses, securing them with marine-grade clamps.
- Open the seacock, reconnect the battery, and start the engine. Check for any leaks (water or exhaust) around the new installation.
Troubleshooting & FAQ
What are the signs my exhaust elbow is failing?
Common signs of a failing mixing elbow include engine overheating, steam or white smoke in the exhaust, reduced water flow from the exhaust outlet, and external water leaks or corrosion on the elbow itself. A clogged elbow can restrict exhaust flow and cause significant engine damage.
Why is this made of stainless steel instead of cast iron like the original?
This aftermarket elbow is upgraded to 316-grade stainless steel for its superior resistance to corrosion and rust from hot, acidic exhaust gases and saltwater. This provides a significantly longer service life compared to the standard cast iron OEM part.
How often should an exhaust elbow be inspected or replaced?
It is good practice to inspect the exhaust elbow annually for signs of corrosion, carbon buildup, or blockage. Replacement intervals vary widely based on usage (salt vs. fresh water, engine hours), but stainless steel versions typically last much longer than their cast iron counterparts.
Is the included gasket important?
Yes, always use the new gasket provided. Re-using an old gasket or not using one at all will cause dangerous exhaust and water leaks, leading to poor engine performance and potential damage to surrounding components.
My engine model is listed, but the part looks different. What should I do?
Do not install the part. Manufacturers sometimes make mid-year changes. Always compare the new part to your old one before installation. Contact us with photos of your original part if you are unsure.
OEM vs. Aftermarket?
This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.
Shipping speed & cost?
We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.
Warranty & returns?
Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.
Safety & Important Info
- Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
- This is an aftermarket replacement, not an OEM component.
- Professional installation is recommended for safety and performance.
About Sea Sierra
- Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
- Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
- Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.
Payment & Security
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
